Xcode 3.0 install problem

[admkazuya]

Hi, Im running 10.5.2 Zephyros on my ML115 and works fine, but i have one problem and need your help
When i installed Xcode 3.0, my system was freeze and i must force power-off.
my system was gone..... and i must reinstall 10.5.2..... :<

any solutions ?