Change Active Partition

I was wondering if anyone knew how to change the active partition. I looked
around for other native ways but wasn't able to find anything.

With a little digging I found a few things with in WMI
Win32_DiskPartition
bootable
bootpartition

the way my system is set now there are two partitions. the active one has
both of those settings to -1 and the other partition (an IBM utility
partition) has the bootable set to nothing and bootpartition to 0

this wasn't something I was just going to experiment with

im open to any suggestions. just need a way to change the active partition.
I was going to try and use FDISK but its not part of XP. I don't mind using
other tools but it needs to be able to run pretty invisibly.

thanks for the help.

Justin