Win 98 Apache - Directory style Query Strings on PHP Files without extensions

Hi, I'm trying to allow my Apache webserver, on Win 98 to run PHP files without extensions. This is all working but the second part to the plan involves changing the query string into the format of a directory. e.g. Where the file is "index" without an extension and "xxx" and "yyy" are the sections of the query string. Although http://www.mysite.com/ or http://www.mysite.com/index work fine, picking up the index file okay http://www.mysite.com/xxx/yyy/ or http://www.mysite.com/index/xxx/yyy/ come back with internal server errors. I have set the DirectoryIndex to "index" and DefaultType to "application/x-httpd-php" in the httpd.conf but I am at a loss after that! If anyone can help I'd be much obliged. Andy