adding validator strategy for XML content type now.
diff --git a/bundles/org.eclipse.wst.xml.ui/src/org/eclipse/wst/xml/ui/StructuredTextViewerConfigurationXML.java b/bundles/org.eclipse.wst.xml.ui/src/org/eclipse/wst/xml/ui/StructuredTextViewerConfigurationXML.java
index a208675..e2850cb 100644
--- a/bundles/org.eclipse.wst.xml.ui/src/org/eclipse/wst/xml/ui/StructuredTextViewerConfigurationXML.java
+++ b/bundles/org.eclipse.wst.xml.ui/src/org/eclipse/wst/xml/ui/StructuredTextViewerConfigurationXML.java
@@ -234,6 +234,14 @@
 					fReconciler.setReconcilingStrategy(xmlStrategy, StructuredTextPartitionerForXML.ST_DEFAULT_XML);
 					fReconciler.setDefaultStrategy(defaultStrategy);
 
+					//----------------------------------------------------------------------------------
+					// valdator extension point
+					//----------------------------------------------------------------------------------
+					String contentTypeId = sModel.getContentTypeIdentifier();
+					if(contentTypeId != null)
+						fReconciler.setValidatorStrategy(createValidatorStrategy(contentTypeId));
+					//----------------------------------------------------------------------------------
+					
 					reconcilerStrategiesAreSet = true;
 				}
 			} finally {