free-hand fix for a CCE seen in the logs:
java.lang.ClassCastException: org.eclipse.jdt.internal.compiler.lookup.BlockScope cannot be cast to org.eclipse.jdt.internal.compiler.lookup.MethodScope
        at org.eclipse.objectteams.otdt.internal.core.compiler.lookup.CallinCalloutScope.maybeReResolveReference(CallinCalloutScope.java:131)
        at org.eclipse.jdt.core.dom.DefaultBindingResolver.resolveName(DefaultBindingResolver.java:1438)
        at org.eclipse.jdt.core.dom.Name.resolveBinding(Name.java:87)
        at org.eclipse.jdt.internal.ui.search.OccurrencesFinder.visit(OccurrencesFinder.java:167)
diff --git a/org.eclipse.jdt.core/compiler/org/eclipse/objectteams/otdt/internal/core/compiler/lookup/CallinCalloutScope.java b/org.eclipse.jdt.core/compiler/org/eclipse/objectteams/otdt/internal/core/compiler/lookup/CallinCalloutScope.java
index e4a042e..9a9b155 100644
--- a/org.eclipse.jdt.core/compiler/org/eclipse/objectteams/otdt/internal/core/compiler/lookup/CallinCalloutScope.java
+++ b/org.eclipse.jdt.core/compiler/org/eclipse/objectteams/otdt/internal/core/compiler/lookup/CallinCalloutScope.java
@@ -128,7 +128,7 @@
 			&& localBinding.declaringScope.isMethodMappingWrapper()) 		// defined in a method mapping wrapper
 		{
 			// hide internal local var but re-resolve:
-			CallinCalloutScope mappingScope = ((MethodScope)localBinding.declaringScope).getDeclaringMappingScope();
+			CallinCalloutScope mappingScope = localBinding.declaringScope.methodScope().getDeclaringMappingScope();
 			if (mappingScope != null)
 				binding = mappingScope.getSurfaceBinding(singleNameReference, singleNameReference.baseclassDecapsulation.isAllowed());
 		}