I stumbled upon a build of dosbox that runs great on the X50v. Granted, it doesn't have sound and the mouse is a little hokey, but it seems to run fairly fast.
http://www.geocities.com/pdosbox/details.htm
If you configure it before running it, you can get it to work pretty well. However, it doesn't have a software keyboard of its own so you have to use the standard windows mobile keyboard.
I emailed the guy who made it, and he basically said that very few people know about it because he's not advertising it. Personally, I think the word needs to get out since it actually works for my X50v.