non destruction repartitioning tool?

[neoplasticity]

im about to install ubuntu on my imac 333/rev d.

is there a nondestructive repartitioning tool?

if there isn't, what do i install first on a freshly partitioned drive? os x or ubuntu?

thanks

[hatefulthreatening]

GNU Parted did the trick for me. Disable journalling in OS X using disk utility first.