Problem with compound path clipping

I have a compound path, which I want to use as a clipping path.

so, I set the "clipping" property of it's child pathItems to "true", then added them all to a clipped layer, as the following code snippet shows:

             // get the image to be clipped

         var placedArtItem = templateDoc.groupItems.createFromFile(artFileRef );

         // get the clipping path and set it to clipping

         var backClipPath = artLayer.compoundPathItems[0];   
         backClipPath.pathItems[0].clipping = true

         // group and clip
         var clippingGroup = artLayer.groupItems.add();
         clippingGroup.name = "clip Group";

         backClipPath.move(clippingGroup , ElementPlacement.PLACEATEND );
         placedArtItem.move( clippingGroup , ElementPlacement.PLACEATEND );

         clippingGroup.clipped = true;

this way, is working great in case the path is normal pathItem and not a compoundPathItem.

But with compoundPathItem, it only group but don't clip, do any one know how to do it with compoundPathItem.