Sometime we have to ensure that mysql support is enabled inside php configuration and is working. In higher version of PHP, mysql support is integrated so no need to manually enable them from config file.
However we can check the status of mysql support by using phpinfo function before going for phpmyadmin or any other tools. This is what we will get if we scroll down a bit from phpinfo display screen.
We are running MySQL 5.0.24 with PHP 5.0.3 , this is a part of the display of phpinfo function.