[news.eclipse.modeling.gmf] Decorator provider problem

["d3K4!n" <zuegg@xxxxxxxxxx>]

Hi,
I'm trying to add a custom decoration to an editpart using the 
decoratorProviders extension point in the diagram plugin.xml.
The problem is that my provider class  is never used (the methods 
createDecorators and provides are never called).

Here is the extension point I added (following the ReviewDecorator example):

<extension 
id="it.lynx.intesa.ide.modeler.visualmodel.diagram.VisualmodelDecoratorProvider"
         name="Diagram Decorator Provider"
         point="org.eclipse.gmf.runtime.diagram.ui.decoratorProviders">
      <decoratorProvider 
class="it.lynx.intesa.ide.modeler.visualmodel.diagram.VisualmodelDecoratorProvider">
         <Priority name="Lowest"/>
         <object 
class="it.lynx.intesa.ide.model.visualModel.diagram.edit.parts.VPagePageNameEditPart"
               id="PAGE_LINK"/>
         <context decoratorTargets="PAGE_LINK"/>
     </decoratorProvider>
</extension>

It should work but I'm not able to realize where is the problem :(

Thanks for any suggestion,
Massimo.