Actually, a lot of hosts do not allow changing of the servers sql password within phpmyadmin (as with creating a new database) and it needs to be changed within the hosts control panel itself.
As for within threads, you can just adjust the config file manually, or the option within the configuration pages (I don't have a .t install available to me at the current moment to lookup the exact location offhand, but it should be one of the first links in the .t control panel).
