I installed gtk+2.4.9 on my ppc64 2004.2 successfully, but in Gnome I had a probelm with cursor keys: keys <up> and <down> didnt function as expected, actually they were just like <right> and <left> keys. I tried many gtk+ based apps, all had the same problem. So I reverted to gtk+2.4.4, the problem went away.
*** This bug has been marked as a duplicate of 64359 ***
closing...