diff --git a/tests/org.eclipse.wst.jsdt.core.tests.compiler/src/org/eclipse/wst/jsdt/core/tests/compiler/regression/InferTypesTests.java b/tests/org.eclipse.wst.jsdt.core.tests.compiler/src/org/eclipse/wst/jsdt/core/tests/compiler/regression/InferTypesTests.java
index 1d0c9a2..5cf78e8 100644
--- a/tests/org.eclipse.wst.jsdt.core.tests.compiler/src/org/eclipse/wst/jsdt/core/tests/compiler/regression/InferTypesTests.java
+++ b/tests/org.eclipse.wst.jsdt.core.tests.compiler/src/org/eclipse/wst/jsdt/core/tests/compiler/regression/InferTypesTests.java
@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2005, 2008 IBM Corporation and others.
+ * Copyright (c) 2005, 2010 IBM Corporation and others.
  * 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
@@ -935,7 +935,8 @@
 			 );
 		}
 		
-		public void testBUG286010() {
+		public void test098() {
+			// BUG286010
 			CompilationUnitDeclaration declaration = this.runInferTest(
 				"var MyFunc = function () {};\n" +
 				"MyFunc.myMeth = function () {};",
@@ -945,4 +946,77 @@
 				
 			 );
 		}		
+
+		public void test099() {
+			// BUG278904
+			CompilationUnitDeclaration declaration = this.runInferTest(
+				"function MyType(){}"+
+				"MyType.prototype = new Object();\n"+
+				"/**\n"+
+				"  * Property length\n"+
+				"  * @type    Number\n"+
+				"  * @memberOf   MyType\n"+
+				"  * @see     MyType\n"+
+				"  * @since   WTP 3.2.2\n"+
+				" */\n"+  
+				"MyType.prototype.length = \"\";\n",
+				"X.js",
+				"class MyType extends Object{\n  Number length;\n  MyType()\n}\n",
+				getDefaultOptions()
+				
+			 );
+		}		
+		public void test100() {
+			// BUG278904
+			CompilationUnitDeclaration declaration = this.runInferTest(
+				"function MyType(){}"+
+				"MyType.prototype = new Object();\n"+
+				"/**\n"+
+				"  * Property length\n"+
+				"  * @memberOf   MyType\n"+
+				"  * @see     MyType\n"+
+				"  * @since   WTP 3.2.2\n"+
+				" */\n"+  
+				"MyType.prototype.length = \"\";\n",
+				"X.js",
+				"class MyType extends Object{\n  String length;\n  MyType()\n}\n",
+				getDefaultOptions()
+				
+			 );
+		}		
+		public void test101() {
+			CompilationUnitDeclaration declaration = this.runInferTest(
+				"MyType = {\n"+
+				"/**\n"+
+				"  * Property length\n"+
+				"  * @type    Number\n"+
+				"  * @memberOf   MyType\n"+
+				"  * @see     MyType\n"+
+				"  * @since   WTP 3.2.2\n"+
+				" */\n"+  
+				"length : \"value\"\n"+
+				"};",
+				"X.js",
+				"class MyType extends Object{\n  Number length;\n}\n",
+				getDefaultOptions()
+				
+			 );
+		}		
+		public void test102() {
+			CompilationUnitDeclaration declaration = this.runInferTest(
+				"MyType = {\n"+
+				"/**\n"+
+				"  * Property length\n"+
+				"  * @memberOf   MyType\n"+
+				"  * @see     MyType\n"+
+				"  * @since   WTP 3.2.2\n"+
+				" */\n"+  
+				"length : \"value\"\n"+
+				"};",
+				"X.js",
+				"class MyType extends Object{\n  String length;\n}\n",
+				getDefaultOptions()
+				
+			 );
+		}		
 }