default python when multiple python installation on the box

[j_nwb]

HI
   I have multiple python installations. 2.2, 2.3, 2.4. When I install a
new package (pygtk2) , it always install in python 2.3.
   I changed the /usr/bin/python to be 2.4 binary. Still the same behavior.
   How does rpms, determine which installation to update ? Is there a
file somewhere ?
 I am running in to this on Fedora as well as CenOS.

Thanks
/J