Translating folders in URLs into query strings without Custom Error handler

[Vince C.]

Hi.

My web site is entirely based on XML/XSL. Transformation of XML into HTML is a
server-side process. All my URLs are like this:
http://host/Application/?Document=AnyDoc&Chapter=3. There is only one script,
default.asp, in the root web that processes requests and displays HTML content
based on the query string.

I'd like to intercept calls to http://host/Application/Catalog and translate
into http://host/Application/?Document=Catalog before it is passed to the custom
error 404 handler. Can it be done - do I need a HTML filter or something?

Thanks for any hint/suggestion.

Vince C.