Note the "translucent" sprite on the bottom of the screen. Bottom part of the weapon seems missing (or the sprite is moved upwards?). It happens in Hexen as well as Doom2. Switching between fullscreen HUD and traditional hud (with the horizontal bar) doesn't help.
By the way I don't know where to find the SVN revision number. I've found my vavoom here:
<!-- m --><a class="postlink" href="http://vavoom.svn.sourceforge.net/viewvc/vavoom/trunk/vavoom/">http://vavoom.svn.sourceforge.net/viewv ... nk/vavoom/</a><!-- m --> (Download GNU Tarball)