MySQL module isn't supported by PHP.

This error message is displayed when you haven't installed or activated the MySQL library used by PHP. Try to find the mysql.so file by using the following command:

find / -name mysql.so

 When you find this file, activate the extension in your php.ini file (this file is usually located in the directory /etc/php4/apache/) by typing option:

extension=mysql.so

You can use Midnight command (mc) program to edit this file. If you don't find the mysql.so file, try to install a new package php4-mysql (package name php4-mysql is used by Debian, in Fedora distribution it will be found with the same or similar to the Debian's name).