[Zope] How to avoid repeated records from an OR search in ZCatalog?

As suggested by Caseman, it's possible in Zope 2.3 to do OR searches across different indexes using Zcatalog. Like this: <dtml-in expr="catalog(title=query) + catalog(summary=query)+ catalog(body=query) + catalog(notes=query)"> ........... </dtml-in> The problem is that if the queried word is found at more than one index, then its correspondant record will appear repeated as many times as the number of indexes for the same document. Has anybody dealed with this before? Is there a workaround (not using PrincipiaSearchSource)? Thanks in advance, Ausum