Hi, the problem is most probably that you are using old version of php with a newer version fo mysql
it might have accured while trying to connect to mysql 4.1 or 5.0 with an old version of php.
Solution: upgrade your php to one of the latest branches: 5.0.5 or 5.1.1 (note there are some huge differences and BC might be broken somewhere)
Another scenario is that you are trying to connect to mysql 5.0 with php_mysql extension
The problem is that you will need php_mysqli extension to connenct to mysql 5.0
php_mysqli is an exstended mysql module. it is a vailable for php5.0 and newer
note that you will need to configure the use of mysqli in phpmyadmin config.inc.php file
You will also have to enable it on your server.