This has been discussed weeks ago, both here and in the LG Optimus 7 dev board. Yes, this is possible through the built-in registry editor, and no Chevron or certificate by email is needed. The registry editor is a little spartan, but works flawlessly, and can change just about any key or entry.
The only other device I know, or I think I know that has a registry editor is Dell Venue Pro...right? If so, someone should give this a try on their DVP...
LG Optimus 7 E900h [NoDo-Unlocked] <3
Nexus One </3