TFS proper context menu for extension menu item

Hi all

I am trying to properly add a menu item to TFS-> History -> Label context menu using Extensions Package. In the same package I have another menu item intended for the main TFS context menu that uses parent 

<GuidSymbol name="guidSourceControlExplorerMenuGroup" value="{ffe1131c-8ea1-4d05-9728-34ad4611bda9}">
      <IDSymbol name="SourceControlExplorerMenuGroupId" value="0x1111" />

and works smoothly.

I am trying to find the proper ID for the specific context menu. Using the trick to enable menu debug information, ctrl+shift and right click on a label I get this



I have tried al the possible combinations to define a proper additional IdSymbol:

<IDSymbol name="LabelsMenuGroupId" value="??????"/> to use as parent for this new menu item that needs to go in the label context menu, but with no luck.

Any ideas would be greatly appreciated. I hate having to fall back to getting context menus on loading the package and manually add the command details instead of using the template.

Thanks in advance

Kostas

1+1 = 3 for large values of 1