I have long since ditched MySQL 4, and about a year ago I stopped installing the plain MySQL libraries with PHP. (Mostly, they are a pain to install when you are custom building MySQL 5 and PHP 5 on 64 bit architecture, but I digress…)
However, not having access to the plain mysql_* functions makes Wordpress very sad. In WP2.3 there was a work around that was pretty painful, involving some core editing. However, between then and WP2.5, the meek sobbing of folk like myself have been heard!
Simply download this updated db.php and place it in at wp-content/db.php.
You’re done. No really. That’s it! From what I can tell this should even work for fresh installs, not just current installs. If you find anything broken with it, let me know and I’ll give it an update.
Update! I’ve updated to work with Wordpress 2.8.4. You can get the new db.php file here: http://jrm.cc/extras/wp-mysqli-2.8-db.txt