apache problem

Okay, I'm having a most curious problem. I'm trying to configure apache to not include the version and os information in the error pages. When i set ServerSignature to Off in the commonhttpd.conf file, it somehow screws up apache's ability to use php pages proberly, and basically shows all the php source that should be run through the interpreter first. If I set the signature back to On, the problem is fixed. I'm wondering why this is happening, or what could be causing it. If its any help to anyone who might have some insight, the version of apache is 1.3.26 and mod_php 4.2.3.

You could create custom error pages that don't include the server sig. That would prevent it from showing in the error pages but it would still be possible to retrieve the server sig from the headers with just a little more effort by an interested party.

Yes I would also suggest using custom error pages(404, etc...)