I'm not aware of any program like that on the Mogul, but you could get the same effect by calling sprint and having them suspend the ESN. The phone will cease to work and no one else will be able to activate it on their line until the suspension is removed.
Edit: Just saw this in another post. Looks like you would be able to remote lock.
http://www.spritesoftware.com/store/...r-HMP-MoreLink