Do your homework:
http://pcgamingwiki.com/wiki/Renegade_X ... _.28FOV.29
Alternatively you can open
\Renegade X\UDKGame\Config\UDKEngine.ini and set
AspectRatioAxisConstraint= to maintain Y FOV instead of X.
Either way, in first-person view the weapon models will remain Vert-. Maybe HaYDeN or some other UE3 specialist will have a better solution when the beta is over.