This seems odd. I partitioned the disk throught the utility. When I tried installing Windows XP, the partition I created did not show and the screen asked me if I wanted to delete the partition and create a new one to install XP on. What is weird is that I did this thinking this was the part I created and I was not able to boot to the mac partition. That part is silly because in the partition window on the mac side, the screen said the mac partition could not be erased. So how did I end up here haha?
I really don't know, but if you are using Lion you can't install XP - only Windows 7. When you do this again, if you do, then first print out the Boot Camp Assistant's documentation.
Windows does not make formatting easy, so you must be careful when choosing the partition not to choose the OS X partition.