Create 8.3 name for an existing directory

http://technet.microsoft.com/en-us/library/bb490642.aspx:

 fsutil file setshortname <PathName> <shortname>

This worked, but required me to boot into recovery console (on win 7 this is via tapping F8 before you boot.) Also required me to navigate to the disk in question, and run this first:

fsutil behavior set disable8dot3 0