I think in q3 is possible to change the fov with the config.
I saw some in game shots with fov modified, and in some of them things were looking wrong, but this was caused by the fov enlarged to see a wider area, so the things that in real world should be at your sides, were at the borders of the monitor, generating a strange effect, expecially during movements, like when you read a newspaper with a lens.
The point is that we don't want to enlarge the fov, but to reduce it, so the question remains: are those weird effects related to the engine that can't handle without problems different fovs, or simply it looks different and unusual? I dare the first thing from what bob said, but I'd like to see some pics:)