It does work for WOTLK beta. From reading the carbonite forums, if you are playing on beta servers you don't need to get it verified, so afaik you dont need any special config/crack etc to use it on beta.Regarding the Carbo and WotLK, i have noticed the Carbo checks for the WoW version, and it has some special handling for the case if the version is 3.0.1 or higher. I didn't dig into that any deeper so i guess this version of the Carbo just wont work in WoTLK at all.
DynomiteKid might have been playing on the Murmur beta realm? which is now supported in version 1.82