http://www.helpdesksys.com/joomla-articles/27-maximum-execution-time-of-300-seconds.html
Fatal error: Maximum execution time of 300 seconds exceeded
PHPMyAdmin will not work for uploading large mysql databases. If you attempt to upload a large mysql dataset you will often get this error
Here is the Fix
If you get this error you will need edit config.default.php inside phpmyadmin folder and look for this line
$cfg[’ExecTimeLimit’] = 300;
and replace with 0 or any larger value
$cfg[’ExecTimeLimit’] = 3600;
Normally it is located at “/usr/local/cpanel/base/3rdparty/phpMyAdmin/libraries/config.default.php”,
Ref: http://24x7servermanagement.com/blog/?p=517