diff --git a/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/internal/resource/CMOF202UMLHandler.java b/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/internal/resource/CMOF202UMLHandler.java
index 6ded70d..9ef6174 100644
--- a/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/internal/resource/CMOF202UMLHandler.java
+++ b/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/internal/resource/CMOF202UMLHandler.java
@@ -8,7 +8,7 @@
  * Contributors:
  *   Kenn Hussey (IBM Corporation, Embarcadero Technologies) - initial API and implementation
  *   Kenn Hussey (Embarcadero Technologies) - 218388
- *   Kenn Hussey (CEA) - 327039
+ *   Kenn Hussey (CEA) - 327039, 366349
  *
  */
 package org.eclipse.uml2.uml.internal.resource;
@@ -21,6 +21,8 @@
 import org.eclipse.emf.ecore.xmi.XMLHelper;
 import org.eclipse.emf.ecore.xmi.XMLResource;
 import org.eclipse.emf.ecore.xmi.impl.EMOFExtendedMetaData;
+
+import org.eclipse.uml2.uml.UMLPackage;
 import org.eclipse.uml2.uml.resource.CMOF2UMLResource;
 import org.eclipse.uml2.uml.resource.UML212UMLResource;
 import org.eclipse.uml2.uml.resource.UML302UMLResource;
@@ -50,7 +52,7 @@
 			&& XMI2UMLResource.XMI_2_1_NS_URI.equals(helper.getURI(prefix))
 			&& attribs != null
 			&& (UML212UMLResource.UML_METAMODEL_NS_URI.equals(extender) || UML302UMLResource.UML_METAMODEL_NS_URI
-				.equals(extender))) {
+				.equals(extender)) || UMLPackage.eNS_URI.equals(extender)) {
 
 			types.push(UML_EXTENSION_TYPE);
 		} else {
diff --git a/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/resource/CMOF2UMLResource.java b/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/resource/CMOF2UMLResource.java
index 8a02ca7..ced3872 100644
--- a/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/resource/CMOF2UMLResource.java
+++ b/plugins/org.eclipse.uml2.uml/src/org/eclipse/uml2/uml/resource/CMOF2UMLResource.java
@@ -8,7 +8,7 @@
  * Contributors:
  *   Kenn Hussey (IBM Corporation) - initial API and implementation
  *   Kenn Hussey (Embarcadero Technologies) - 156879, 218388
- *   Kenn Hussey (CEA) - 327039, 351774
+ *   Kenn Hussey (CEA) - 327039, 351774, 366349
  *
  */
 package org.eclipse.uml2.uml.resource;
@@ -32,11 +32,11 @@
 
 	String CMOF_2_4_METAMODEL_URI = "http://www.omg.org/spec/MOF/20100901/cmof.xmi"; //$NON-NLS-1$
 
-	String CMOF_2_4_METAMODEL_NS_URI = "http://www.omg.org/spec/MOF/20100901"; //$NON-NLS-1$
+	String CMOF_2_4_METAMODEL_NS_URI = CMOF_2_4_METAMODEL_URI;
 
 	String CMOF_2_4_1_METAMODEL_URI = "http://www.omg.org/spec/MOF/20110701/cmof.xmi"; //$NON-NLS-1$
 
-	String CMOF_2_4_1_METAMODEL_NS_URI = "http://www.omg.org/spec/MOF/20110701"; //$NON-NLS-1$
+	String CMOF_2_4_1_METAMODEL_NS_URI = CMOF_2_4_1_METAMODEL_URI;
 
 	String CMOF_METAMODEL_URI = CMOF_2_4_1_METAMODEL_URI;