I'm surprised nobody worked this out already :| Shame on you all!
Here, you can get the hacked emulator so the signature isn't checked, and the region is stored on the xbe (which doesn't need to be signed)
Anybody work it out yet?
Open the xbe in a hex editor
find where the titlename starts
go 0x94 bytes forward, your now at where the region is stored.
Change the byte to:
North America: 01
Everywhere else: 04
Save the file, and you've now successfully changed the region.
also, why was http://www.xboxhacker.org/index.php?topic=14164.0
closed? I was going to reply with this, but I had to make a new thread instead