Even though mysql is set in my USE variables, i could not get php with mysql compiled in. Everytime i pulled up an phpinfo() it showed that mysql was compiled with the option '- -withou-mysql' It took me hours to realize that this is configured by the ebuild and that it wasn't my fault at all. When i looked in the ebuild, there is a part where the with and without options are being set. The mysql line looks like: use mysql && myconf="${myconf} --with-mysql=/usr" || myconf= "${myconf} --without-mysql". i think that a few () are missing there, because when i removed the part after || and emerge'ed, php was compiled with mysql support. Please take a look into this line and check its correctness.
I cannot recreate this... I just tried an upgrade to mod_php 4.2.3 from 4.2.2... Mysql was included in the new build.
Works for me... Please reopen if the problem persists.