What this may mean? and how to fix it? It happens when I'm trying to open gpd.xml There was a problem adding adapter factories loader constraint violation: when resolving method "org.eclipse.wst.xml.core.internal.modelquery.ModelQueryUtil.getModelQuery(Lorg/w3c/dom/Document;)Lorg/eclipse/wst/xml/core/internal/contentmodel/modelquery/ModelQuery;" the class loader (instance of org/eclipse/osgi/internal/baseadaptor/DefaultClassLoader) of the current class, org/eclipse/wst/xml/ui/internal/DOMObserver, and the class loader (instance of org/eclipse/osgi/internal/baseadaptor/DefaultClassLoader) for resolved class, org/eclipse/wst/xml/core/internal/modelquery/ModelQueryUtil, have different Class objects for the type org/w3c/dom/Document used in the signature Thanks. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4112016#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...