[Zope-dev] cataloging binary files (pdf's, word docs...)

I'm trying to come up with a way to catalog PDF's and Word docs. It is easy to write python methods to pull the text ouf of these. The problem is that we already have tons of them in our ZODB as file objects. The only thing I can think of is to make a zclass class for each type (ie. PDFFile type) that has a method that knows how to extract the text from the pdf and have zcatalog catalog that property. But this means re-creating all the binary files currenlty in our ZODB. Can any one offer any better suggestions? I could write a python method that extracted the text based on mime type but I can't go back and ad that method to each file object. Thanks for any help. ^Roman