Index: trunk/autoquest-core-usability/src/main/java/de/ugoe/cs/autoquest/usability/DefaultValueRule.java
===================================================================
--- trunk/autoquest-core-usability/src/main/java/de/ugoe/cs/autoquest/usability/DefaultValueRule.java	(revision 1918)
+++ trunk/autoquest-core-usability/src/main/java/de/ugoe/cs/autoquest/usability/DefaultValueRule.java	(revision 1941)
@@ -593,5 +593,6 @@
             else if (obj instanceof ValueSelectionTarget) {
                 ValueSelectionTarget other = (ValueSelectionTarget) obj;
-                return (other.view.equals(this.view) && other.target.equals(this.target));
+                return ((this.view == null) ? other.view == null : other.view.equals(this.view) &&
+                        other.target.equals(this.target));
             }
             
@@ -603,5 +604,10 @@
          */
         public int hashCode() {
-            return view.hashCode();
+            if (view != null) {
+                return view.hashCode();
+            }
+            else {
+                return 0;
+            }
         }