Ubuntu Geek posted a tutorial about downgrade PHP version from 5.4 to 5.3 in Ubuntu 12.10

Procedure to follow

First you need to download the shell script from here

Once you have php5_4_downgrade_5.3.sh file you need to change the permissions using the following command

  How to Downgrade PHP version from 5.4 to 5.3 in ubuntu 12.10 (Quantal)