Vista & Xp Same Disk

[dimme]

I want to triple boot my macpro with Vista & Xp on the same disk. However bootcamp will not let me make 2 partitions on my second disk. I tried using disk utiity but then windows will not book. Same with the windows installer to resize the disk. Any ideas???

 

[gmontag]

Leave the space as free. Install XP then run vista as an upgrade but tell it to leave the old os. Then allow windows to create the partition from vista installer. This partition will use the windows boot loader in the xp portion to launch vista.

 

[dimme]

Leave the space as free. Install XP then run vista as an upgrade but tell it to leave the old os. Then allow windows to create the partition from vista installer. This partition will use the windows boot loader in the xp portion to launch vista.

Thanks
How do I create the free space. Boot camp only allows me to format the whole disk.