[Zope] Searching through the contents of Pdf/Word/latex

Hi all, I am a zope newbie and currently am using the Portal ToolKit and the external file to build a website. I am facing problem in searching the contents of the external file that i upload [ msword/pdf/latex/... ]. The Zcatalog search does not seem to search and index the contents of pdf/doc/latex files. I have looked into HowTo's and the documentation. But being a zope newbie I am finding it difficult to find a way out. I guess that somewhere while making the catalog one has to use converters(pdftotext....and its like) and probably then use that to index those documents. Has anyone done this before. Regards, Praveen Katiyar