how to ungrade python

Greetings all, I am new to SUSE, but not new to Unix in general. I wanted to know what is the most correct way to downgrade Python 2.4 which was installed as default to 2.3.5. One of the special application needs Python 2.3.5. I installed the 2.3.5 from source without any problem, but YaST doesn't see it. If I removed the 2.4.* using YaST, the Kde desktop stop working. Can anyone give me a hint? Chen