--- a/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/viewers/ObservableViewerElementSet.d	Sat Apr 18 09:25:29 2009 +0200
+++ b/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/viewers/ObservableViewerElementSet.d	Sat Apr 18 13:54:50 2009 +0200
@@ -11,6 +11,7 @@
  ******************************************************************************/
 
 module org.eclipse.jface.internal.databinding.viewers.ObservableViewerElementSet;
+import org.eclipse.jface.internal.databinding.viewers.ViewerElementSet;
 
 import java.lang.all;
 
@@ -62,7 +63,7 @@
             IElementComparer comparer) {
         super(realm);
 
-        Assert.isNotNull(comparer);
+        Assert.isNotNull(cast(Object)comparer);
         this.wrappedSet = new ViewerElementSet(comparer);
         this.elementType = elementType;
         this.comparer = comparer;
@@ -157,7 +158,7 @@
             // Cannot rely on c.contains(element) because we must compare
             // elements using IElementComparer.
             for (int i = 0; i < toRetain.length; i++) {
-                if (comparer.equals(element, toRetain[i]))
+                if (comparer.opEquals(element, toRetain[i]))
                     continue outer;
             }
             iterator.remove();