Ok, I dont know why u want to change the version but remember the protocol for gumps changed around 5. something so you might get messed up gumps if you do it. As Far as doing it, load up your favorite memory sniffer, I think there is a good one called gamer cheater or Olly, search for the exact string of the version and you can change it before the client logs into the server. This should work.
Anyone know of a FREE memory searcher and changer?
Also note, you can use the SDKs search memory proccess thing and construct a system that can search for Ints, Bools, Floats (if there are any), Strings, chars, shorts. That would be leet tool for UO if there isnt one. Extension for the SDK.
Rhymes