Upgrading PHP

Hi, I have this annoying problem and I was hoping it was a familiar thing. I need to upgrade PHP4.0.0 to 4.0.2 (with some extra stuff) and we're running Apache 1.3.12. PHP4.0.0 is a dynamic Apache module and things run fine. When I compile the new PHP4.0.2, though, stop the webserver and install it over the old apache/libexec/libphp4.so (by just doing make install in php-4.0.2/ BTW), then restart the webserver again, none of the webpages work; they all give "Document contains no data". Yeah, you guessed it, the error_log says a child has segfaulted. What I don't know, is why and before I need to debug all kinds of stuff, I wanted to tell you guys this. Anything of this that sounds familiar? Solutions? Ivo