Hi,
I'm experiencing the same problem as you had with SQLite.
Just went back to a project based on SQLite, which used to work on my previous install, and now I have this "Call to undefined function sqlite_open()" showing up.
You say it has something to do with mod_rewrite, but I don't really know about it. Would you be kind enough to explain me how you had it solved ?
I'm running PHP5 with Apache2, all the SQLite support is enabled in phpinfo().
Thanx.