269217 - unable to edit discriminator column
diff --git a/jpa/plugins/org.eclipse.jpt.ui/src/org/eclipse/jpt/ui/internal/mappings/details/DiscriminatorColumnComposite.java b/jpa/plugins/org.eclipse.jpt.ui/src/org/eclipse/jpt/ui/internal/mappings/details/DiscriminatorColumnComposite.java
index 3449659..629c39f 100644
--- a/jpa/plugins/org.eclipse.jpt.ui/src/org/eclipse/jpt/ui/internal/mappings/details/DiscriminatorColumnComposite.java
+++ b/jpa/plugins/org.eclipse.jpt.ui/src/org/eclipse/jpt/ui/internal/mappings/details/DiscriminatorColumnComposite.java
@@ -173,10 +173,10 @@
 	}
 
 	private PropertyValueModel<DiscriminatorColumn> buildDiscriminatorColumnHolder() {
-		return new PropertyAspectAdapter<Entity, DiscriminatorColumn>(getSubjectHolder(), Entity.DISCRIMINATOR_COLUMN_IS_UNDEFINED_PROPERTY) {
+		return new PropertyAspectAdapter<Entity, DiscriminatorColumn>(getSubjectHolder()) {
 			@Override
 			protected DiscriminatorColumn buildValue_() {
-				return this.subject.discriminatorColumnIsUndefined() ? null : this.subject.getDiscriminatorColumn();
+				return this.subject.getDiscriminatorColumn();
 			}
 		};
 	}