partitioning help, Ubuntu on PowerPC

[Alex Dean]

I'm installing Ubuntu on my Powerbook.  I have an 80GB drive, and I'd  
like to give Ubutntu about 20GB of that space.  When I get to the  
'disk partitioning' part of the installation, though, I get pretty  
confused, and I hope someone here can enlighten me.

The disk partitioner lists the following :

IDE1 Master (hda)
#1	32.3kB	Apple
	134.2MB	FREE SPACE
#3	79.9GB	hfs+ Apple_HFS_UN
	8.2kB	FREE SPACE

I seem to remember that when I did this on an Intel machine, it let  
me resize the Windows partition to claim some space for Ubunutu.  But  
here I don't see any options to shrink the size of the main (~80GB)  
partition.  What should I do at this point?

thanks,
alex
.