diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design.ui/src/org/eclipse/datatools/connectivity/oda/design/internal/designsession/DesignSessionUtilBase.java b/plugins/org.eclipse.datatools.connectivity.oda.design.ui/src/org/eclipse/datatools/connectivity/oda/design/internal/designsession/DesignSessionUtilBase.java
index 78bc4e6..114161f 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design.ui/src/org/eclipse/datatools/connectivity/oda/design/internal/designsession/DesignSessionUtilBase.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design.ui/src/org/eclipse/datatools/connectivity/oda/design/internal/designsession/DesignSessionUtilBase.java
@@ -121,8 +121,9 @@
         throws OdaException
     {
         java.util.Properties candidateProps = DesignUtil.convertDataSourceProperties( dataSourceDesign );
-        IPropertyProvider propProvider = 
-            getPropertyProvider( dataSourceDesign.getOdaExtensionDataSourceId() );
+        IPropertyProvider propProvider = null;
+        if( dataSourceDesign != null )
+            propProvider = getPropertyProvider( dataSourceDesign.getOdaExtensionDataSourceId() );
         if( propProvider == null )   // oda data source does not have own provider, use the system default
             propProvider = getPropertyProvider( DEFAULT_PROPERTY_PROVIDER_ID );
         
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/META-INF/MANIFEST.MF b/plugins/org.eclipse.datatools.connectivity.oda.design/META-INF/MANIFEST.MF
index de827be..de25196 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/META-INF/MANIFEST.MF
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/META-INF/MANIFEST.MF
@@ -2,7 +2,7 @@
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.datatools.connectivity.oda.design; singleton:=true
-Bundle-Version: 3.3.2.qualifier
+Bundle-Version: 3.3.3.qualifier
 Bundle-Vendor: %providerName
 Bundle-Localization: plugin
 Export-Package: org.eclipse.datatools.connectivity.oda.design,
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/model/DesignXML.xsd b/plugins/org.eclipse.datatools.connectivity.oda.design/model/DesignXML.xsd
index 161e97c..1008017 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/model/DesignXML.xsd
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/model/DesignXML.xsd
@@ -397,7 +397,7 @@
       <xsd:documentation>A design-time data set definition.</xsd:documentation>
     </xsd:annotation>
     <xsd:sequence>
-      <xsd:element maxOccurs="1" minOccurs="1" name="dataSourceDesign" type="design:DataSourceDesign">
+      <xsd:element maxOccurs="1" minOccurs="0" name="dataSourceDesign" type="design:DataSourceDesign">
         <xsd:annotation>
           <xsd:documentation>The instance of dataSourceDesign that supports this type of data set.  Could be null, if nested within another dataSetDesign, to share the container's dataSourceDesign.</xsd:documentation>
         </xsd:annotation>
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/model/org.eclipse.datatools.connectivity.oda.design.ecore b/plugins/org.eclipse.datatools.connectivity.oda.design/model/org.eclipse.datatools.connectivity.oda.design.ecore
index 0efe75e..8186fa9 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/model/org.eclipse.datatools.connectivity.oda.design.ecore
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/model/org.eclipse.datatools.connectivity.oda.design.ecore
@@ -440,8 +440,8 @@
         <details key="namespace" value="##targetNamespace"/>
       </eAnnotations>
     </eStructuralFeatures>
-    <eStructuralFeatures xsi:type="ecore:EReference" name="dataSourceDesign" lowerBound="1"
-        eType="#//DataSourceDesign" containment="true" resolveProxies="false">
+    <eStructuralFeatures xsi:type="ecore:EReference" name="dataSourceDesign" eType="#//DataSourceDesign"
+        containment="true" resolveProxies="false">
       <eAnnotations source="http://www.eclipse.org/emf/2002/GenModel">
         <details key="documentation" value="The instance of dataSourceDesign that supports this type of data set.  Could be null, if nested within another dataSetDesign, to share the container's dataSourceDesign."/>
       </eAnnotations>
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/DataSetDesign.java b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/DataSetDesign.java
index 99444ec..ddfe876 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/DataSetDesign.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/DataSetDesign.java
@@ -1,6 +1,6 @@
 /**
  *************************************************************************
- * Copyright (c) 2005, 2010 Actuate Corporation.
+ * Copyright (c) 2005, 2011 Actuate Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -11,7 +11,7 @@
  *  
  *************************************************************************
  *
- * $Id: DataSetDesign.java,v 1.7 2009/03/13 05:19:46 lchan Exp $
+ * $Id: DataSetDesign.java,v 1.8 2010/02/17 02:20:40 lchan Exp $
  */
 package org.eclipse.datatools.connectivity.oda.design;
 
@@ -52,7 +52,7 @@
      * <!-- end-user-doc -->
      * @generated
      */
-    String copyright = "Copyright (c) 2005, 2010 Actuate Corporation"; //$NON-NLS-1$
+    String copyright = "Copyright (c) 2005, 2011 Actuate Corporation"; //$NON-NLS-1$
 
     /**
      * Returns the ODA data source element ID of the
@@ -126,7 +126,7 @@
      * @return the value of the '<em>Data Source Design</em>' containment reference.
      * @see #setDataSourceDesign(DataSourceDesign)
      * @see org.eclipse.datatools.connectivity.oda.design.DesignPackage#getDataSetDesign_DataSourceDesign()
-     * @model containment="true" required="true"
+     * @model containment="true"
      *        extendedMetaData="kind='element' name='dataSourceDesign' namespace='##targetNamespace'"
      * @generated
      */
@@ -225,7 +225,7 @@
      * @since 3.2.3
      */
     String getDisplayNameKey();
-    
+
     /**
      * Sets the resource key of the '{@link org.eclipse.datatools.connectivity.oda.design.DataSetDesign#getDisplayName <em>Display Name</em>}' attribute.
      * @param value  the new resource key of the '<em>Display Name</em>' attribute;
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/impl/DesignPackageImpl.java b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/impl/DesignPackageImpl.java
index 4e2bebe..881f75d 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/impl/DesignPackageImpl.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/impl/DesignPackageImpl.java
@@ -1,6 +1,6 @@
 /**
  *************************************************************************
- * Copyright (c) 2005, 2010 Actuate Corporation.
+ * Copyright (c) 2005, 2011 Actuate Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -11,7 +11,7 @@
  *  
  *************************************************************************
  *
- * $Id: DesignPackageImpl.java,v 1.20 2010/08/17 03:57:02 lchan Exp $
+ * $Id: DesignPackageImpl.java,v 1.21 2010/10/15 05:41:37 lchan Exp $
  */
 package org.eclipse.datatools.connectivity.oda.design.impl;
 
@@ -109,7 +109,7 @@
      * <!-- end-user-doc -->
      * @generated
      */
-    public static final String copyright = "Copyright (c) 2005, 2010 Actuate Corporation"; //$NON-NLS-1$
+    public static final String copyright = "Copyright (c) 2005, 2011 Actuate Corporation"; //$NON-NLS-1$
 
     /**
      * <!-- begin-user-doc -->
@@ -3937,7 +3937,7 @@
                 getDataSetDesign_DataSourceDesign(),
                 this.getDataSourceDesign(),
                 null,
-                "dataSourceDesign", null, 1, 1, DataSetDesign.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED ); //$NON-NLS-1$
+                "dataSourceDesign", null, 0, 1, DataSetDesign.class, !IS_TRANSIENT, !IS_VOLATILE, IS_CHANGEABLE, IS_COMPOSITE, !IS_RESOLVE_PROXIES, !IS_UNSETTABLE, IS_UNIQUE, !IS_DERIVED, IS_ORDERED ); //$NON-NLS-1$
         initEReference(
                 getDataSetDesign_Query(),
                 this.getDataSetQuery(),
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignUtil.java b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignUtil.java
index f556069..a6fa931 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignUtil.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignUtil.java
@@ -1,6 +1,6 @@
 /**
  *************************************************************************
- * Copyright (c) 2006, 2010 Actuate Corporation.
+ * Copyright (c) 2006, 2011 Actuate Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -11,7 +11,7 @@
  *  
  *************************************************************************
  *
- * $Id: DesignUtil.java,v 1.19 2010/02/17 02:20:41 lchan Exp $
+ * $Id: DesignUtil.java,v 1.20 2010/03/04 01:27:57 lchan Exp $
  */
 
 package org.eclipse.datatools.connectivity.oda.design.util;
@@ -223,6 +223,9 @@
      */
     public static java.util.Properties convertDataSourceProperties( DataSourceDesign dataSourceDesign )
     {
+        if( dataSourceDesign == null )
+            return new java.util.Properties();
+
         java.util.Properties publicProps = convertDesignProperties( 
                 dataSourceDesign.getPublicProperties() );
         java.util.Properties propCollection = convertDesignProperties( 
diff --git a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignValidator.java b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignValidator.java
index 572d347..bc1a97c 100644
--- a/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignValidator.java
+++ b/plugins/org.eclipse.datatools.connectivity.oda.design/src/org/eclipse/datatools/connectivity/oda/design/util/DesignValidator.java
@@ -1,6 +1,6 @@
 /*
  *************************************************************************
- * Copyright (c) 2006, 2007 Actuate Corporation.
+ * Copyright (c) 2006, 2011 Actuate Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -40,7 +40,7 @@
     protected boolean validate_MultiplicityConforms( EObject eObject, 
                                     EStructuralFeature eFeature, 
                                     DiagnosticChain diagnostics, 
-                                    Map context )
+                                    Map<Object, Object> context )
     {        
         // use extended validator method for selected ODA Design classes
         if( isDataSetQueryObject( eObject ) )
@@ -48,6 +48,11 @@
             return validate_DataSetQuery_MultiplicityConforms( eObject, eFeature, 
                     diagnostics, context );
         }
+        else if( isDataSetDesignObject( eObject ) )
+        {
+            return validate_DataSetDesign_MultiplicityConforms( eObject, eFeature, 
+                    diagnostics, context );
+        }
         
         // use default validator
         return super.validate_MultiplicityConforms( eObject, eFeature, 
@@ -63,12 +68,20 @@
     }
     
     /**
+     * Determines whether the specific EObject is a DataSetDesign type.
+     */
+    private boolean isDataSetDesignObject( EObject eObject )
+    {
+        return ( eObject.eClass() == DesignPackage.Literals.DATA_SET_DESIGN );
+    }
+   
+    /**
      * Specialized validator for the DataSetQuery EObject.
      */
     protected boolean validate_DataSetQuery_MultiplicityConforms( EObject eObject, 
                                     EStructuralFeature eFeature, 
                                     DiagnosticChain diagnostics, 
-                                    Map context )
+                                    Map<Object, Object> context )
     {
         if( isDataSetQueryObject( eObject ) &&
             eFeature.isRequired() )
@@ -80,14 +93,7 @@
             if( diagnostics != null )
             {
                 diagnostics.add(
-                    new BasicDiagnostic( Diagnostic.WARNING,
-                            DIAGNOSTIC_SOURCE,
-                            EOBJECT__EVERY_MULTIPCITY_CONFORMS,
-                            getEcoreResourceLocator().getString(
-                                "_UI_RequiredFeatureMustBeSet_diagnostic", //$NON-NLS-1$
-                                new Object[] { getFeatureLabel( eFeature, context), 
-                                                getObjectLabel( eObject, context ) } ),
-                            new Object[] { eObject, eFeature } ));
+                    newRequiredFeatureDiagnostic( Diagnostic.WARNING, eObject, eFeature, context ));
             }
             return true;    // ok to continue with validation
         }
@@ -97,4 +103,51 @@
                                         diagnostics, context );
     }
     
+    /**
+     * Specialized validator for the DataSetDesign EObject.
+     */
+    protected boolean validate_DataSetDesign_MultiplicityConforms( EObject eObject, 
+                                    EStructuralFeature eFeature, 
+                                    DiagnosticChain diagnostics, 
+                                    Map<Object, Object> context )
+    {
+        // validating the DataSourceDesign attribute in a DataSetDesign object
+        if( isDataSetDesignObject( eObject ) && 
+            eFeature.getFeatureID() == DesignPackage.DATA_SET_DESIGN__DATA_SOURCE_DESIGN )
+        {
+            if( eObject.eIsSet( eFeature ) )
+                return true;    // is valid; optional attribute is set
+            
+            // a DataSourceDesign is optional only when its containing DataSetDesign 
+            // is contained by a DynamicValuesQuery
+            if( eObject.eContainer().eClass() == DesignPackage.Literals.DYNAMIC_VALUES_QUERY )
+                return true;
+
+            // required attribute is not set
+            if( diagnostics != null )
+            {
+                diagnostics.add(
+                    newRequiredFeatureDiagnostic( Diagnostic.ERROR, eObject, eFeature, context ));
+            }
+            return false;   
+        }
+        
+        // use default validator implementation for other attributes/features
+        return super.validate_MultiplicityConforms( eObject, eFeature, 
+                                        diagnostics, context );        
+    }
+    
+    private BasicDiagnostic newRequiredFeatureDiagnostic( int severity, 
+                EObject eObject, EStructuralFeature eFeature, Map<Object, Object> context)
+    {
+        return new BasicDiagnostic( severity,
+                    DIAGNOSTIC_SOURCE,
+                    EOBJECT__EVERY_MULTIPCITY_CONFORMS,
+                    getEcoreResourceLocator().getString(
+                        "_UI_RequiredFeatureMustBeSet_diagnostic", //$NON-NLS-1$
+                        new Object[]{ getFeatureLabel( eFeature, context), 
+                                        getObjectLabel( eObject, context )} ),
+                    new Object[] { eObject, eFeature } );        
+    }
+    
 }
diff --git a/releng/org.eclipse.datatools.connectivity.releng/maps/connectivity-plugins.map b/releng/org.eclipse.datatools.connectivity.releng/maps/connectivity-plugins.map
index 81ffd18..51a40e6 100644
--- a/releng/org.eclipse.datatools.connectivity.releng/maps/connectivity-plugins.map
+++ b/releng/org.eclipse.datatools.connectivity.releng/maps/connectivity-plugins.map
@@ -10,8 +10,8 @@
 plugin@org.eclipse.datatools.connectivity.oda.profile=v201007150318,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.profile
 plugin@org.eclipse.datatools.connectivity.oda.flatfile=v201101261152,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.flatfile
 plugin@org.eclipse.datatools.connectivity.oda.flatfile.ui=v201101261152,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.flatfile.ui
-plugin@org.eclipse.datatools.connectivity.oda.design=v201012150952,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.design
-plugin@org.eclipse.datatools.connectivity.oda.design.ui=v201102261335,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.design.ui
+plugin@org.eclipse.datatools.connectivity.oda.design=v201103090701,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.design
+plugin@org.eclipse.datatools.connectivity.oda.design.ui=v201103090701,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.design.ui
 plugin@org.eclipse.datatools.connectivity.oda.consumer=v201102051101,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.connectivity/plugins/org.eclipse.datatools.connectivity.oda.consumer
 plugin@org.eclipse.datatools.help=v200906020553,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.build/org.eclipse.datatools.help
 plugin@org.eclipse.datatools.oda.cshelp=v200907031118,:ext:xgu@dev.eclipse.org:/cvsroot/datatools,,org.eclipse.datatools.build/org.eclipse.datatools.oda.cshelp
diff --git a/tests/org.eclipse.datatools.connectivity.oda.design.tests/META-INF/MANIFEST.MF b/tests/org.eclipse.datatools.connectivity.oda.design.tests/META-INF/MANIFEST.MF
index 5aa0f76..d3afaa5 100644
--- a/tests/org.eclipse.datatools.connectivity.oda.design.tests/META-INF/MANIFEST.MF
+++ b/tests/org.eclipse.datatools.connectivity.oda.design.tests/META-INF/MANIFEST.MF
@@ -7,7 +7,7 @@
 Bundle-Vendor: Eclipse.org
 Export-Package: org.eclipse.datatools.connectivity.oda.design.tests
 Require-Bundle: org.eclipse.core.runtime;bundle-version="[3.3.0,4.0.0)",
- org.eclipse.datatools.connectivity.oda.design;bundle-version="[3.2.3,4.0.0)";visibility:=reexport,
+ org.eclipse.datatools.connectivity.oda.design;bundle-version="[3.3.3,4.0.0)";visibility:=reexport,
  org.eclipse.emf.ecore.xmi;bundle-version="[2.4.0,3.0.0)";visibility:=reexport,
  org.junit;bundle-version="[3.8.2,4.0.0)";visibility:=reexport
 Eclipse-LazyStart: true
diff --git a/tests/org.eclipse.datatools.connectivity.oda.design.tests/src/org/eclipse/datatools/connectivity/oda/design/tests/DesignUtilLoadSaveTest.java b/tests/org.eclipse.datatools.connectivity.oda.design.tests/src/org/eclipse/datatools/connectivity/oda/design/tests/DesignUtilLoadSaveTest.java
index e91451d..a13b930 100644
--- a/tests/org.eclipse.datatools.connectivity.oda.design.tests/src/org/eclipse/datatools/connectivity/oda/design/tests/DesignUtilLoadSaveTest.java
+++ b/tests/org.eclipse.datatools.connectivity.oda.design.tests/src/org/eclipse/datatools/connectivity/oda/design/tests/DesignUtilLoadSaveTest.java
@@ -1,6 +1,6 @@
 /*
  *************************************************************************
- * Copyright (c) 2007, 2010 Actuate Corporation.
+ * Copyright (c) 2007, 2011 Actuate Corporation.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
@@ -37,7 +37,9 @@
 import org.eclipse.datatools.connectivity.oda.design.DataSetParameters;
 import org.eclipse.datatools.connectivity.oda.design.DataSourceDesign;
 import org.eclipse.datatools.connectivity.oda.design.DesignFactory;
+import org.eclipse.datatools.connectivity.oda.design.DesignSessionResponse;
 import org.eclipse.datatools.connectivity.oda.design.DynamicFilterExpression;
+import org.eclipse.datatools.connectivity.oda.design.DynamicValuesQuery;
 import org.eclipse.datatools.connectivity.oda.design.ExpressionArguments;
 import org.eclipse.datatools.connectivity.oda.design.ExpressionParameterDefinition;
 import org.eclipse.datatools.connectivity.oda.design.ExpressionVariable;
@@ -243,7 +245,7 @@
 
         ExpressionArguments exprArgs2 = DesignFactory.eINSTANCE.createExpressionArguments();
         newStaticParamDefn = exprArgs2.addStaticParameter( "static value 1" ); //$NON-NLS-1$
-        newStaticParamDefn.addStaticValue( "static value 2 " );        
+        newStaticParamDefn.addStaticValue( "static value 2 " );         //$NON-NLS-1$
         customExpr2.setContextArguments( exprArgs2 );
 
         assertTrue( newStaticParamDefn.hasEffectiveStaticValues() );
@@ -259,7 +261,7 @@
         dynamicFilterExpr.setIsOptional( false );
         FilterExpressionType defaultType = DesignFactory.eINSTANCE.createFilterExpressionType();
         defaultType.setDeclaringExtensionId( filterExprExtId );
-        defaultType.setId( "10005" );
+        defaultType.setId( "10005" ); //$NON-NLS-1$
         dynamicFilterExpr.setDefaultType( defaultType );
         assertEquals( defaultType, dynamicFilterExpr.getDefaultType() );
         
@@ -472,8 +474,7 @@
         }
         assertTrue( hasException );
     }
-
-    
+   
     public void testAddResourceFileName()
     {
         File goldenFile = new File( getSampleDbTestFilePath() );
@@ -497,6 +498,55 @@
         assertTrue( hasException );        
     }
     
+    public void testNullDataSourceDesignRef()
+    {
+        File goldenFile = new File( getSampleDbTestFilePath() );
+        OdaDesignSession design = loadOdaDesignSession( goldenFile );
+        DataSetDesign dataSetDesign = design.getResponseDataSetDesign();
+
+        dataSetDesign.setDataSourceDesign( null );
+        
+        // test invalid null DataSourceDesign reference
+        DesignSessionResponse designResponse = design.getResponse();
+        boolean hasException = false;
+        try
+        {
+            DesignUtil.validateObject( designResponse );
+        }
+        catch( IllegalStateException ex )
+        {
+            hasException = true;
+        }
+        assertTrue( hasException );
+        
+        // test valid null DataSourceDesign reference in DynamicValuesQuery
+        design = loadOdaDesignSession( goldenFile );    // reload original content
+        dataSetDesign = design.getResponseDataSetDesign();
+        DataSetParameters dataSetParams = dataSetDesign.getParameters();
+        for( ParameterDefinition aParamDefn : dataSetParams.getParameterDefinitions() )
+        {           
+            DataSetDesign nestedDataSetDesign = (DataSetDesign) EcoreUtil.copy( dataSetDesign );
+            nestedDataSetDesign.setDataSourceDesign( null );    // set nested data set to reference a null data source
+
+            DynamicValuesQuery dynamicQuery = DesignFactory.eINSTANCE.createDynamicValuesQuery();
+            dynamicQuery.setDataSetDesign( nestedDataSetDesign );
+            dynamicQuery.setValueColumn( "1" ); //$NON-NLS-1$
+
+            InputElementAttributes inputElementAttrs = aParamDefn.getInputAttributes().getElementAttributes();
+            inputElementAttrs.setDynamicValueChoices( dynamicQuery );           
+        }
+        // test the null reference in this case is valid 
+        designResponse = design.getResponse();
+        try
+        {
+            DesignUtil.validateObject( designResponse );
+        }
+        catch( IllegalStateException ex )
+        {
+            fail();     // not expecting a validation error
+        }  
+    }
+   
     private void saveDesignSession( OdaDesignSession design, File tempOut )
     {
         try