Failed to install ATI Driver through Additional Drivers on Ubuntu

Hi Experts,
My machine is running with Ubuntu 12.04LTS. While installing ATI driver through Additional Drivers I received an error message. It failed to install the driver. I checked the log file. I do not understand the reason behind it.
Please help.

Sorry, installation of this driver failed.
Please have a look at the log file for details: /var/log/jockey.log
