In IIS Version 5, I have PHP filtering .htm and .html documents. In doing so this has disabled the global 404 error page, in other words "This page cannot be found" that is returned by IIS. It now returns either a warning that the document was not found, or a blank page when logging is turned off. My project is going to be solely based on the 404 error page that will gather information on the user, pick one of many Graphical User Interfaces, set the page that they were trying to access as a variable, and either compile a proceeding page found in a private directory such as c:\private\ if found, or compile a custom error page with the graphical user interface.

In basic terms, PHP4 returns it's own 404 error page, and this is bad :P

*note*
I have been talking with several smart people in #php on effnet (IRC) all day and they have no clue, as do I from reading the manual many times.

Thanks.