I have one drive that has three partitions (Vista Bus, Vista x86, & Vista x64) that I can boot from. When I originally created them I made the Vista x64 partition a lot larger then I needed to and the Vista x86 smaller then I should have.

With service pack 1 coming out in the next few weeks, I wanted to increase the size of my Vista x86 partition so I booted my system to one of the partitions I wasn't trying to adjust then, using the 'Disk Management' tool in Vista, I was able to shrink the Vista x64 partition by 23GB. When I try to extend the Vista x86 partition, the 'Extend Volume' option is grayed out.

I then opened 'Diskpart' in a command prompt window and tried extending it by 20GB that way but that tells me there not enough available space on the drive even though both the Disk Management and Diskpart utilities tell me I've got 23GB of free space.

What do I need to do to add the free space to my Vista x86 partition? I've attached a screen shot of what the disk allocation looks like in Disk Management.
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