it might help any helpful people if you were to post some things, like what mods your using, what patch version etc.... It's really hard to help you when you have no information included (even though i doubt i could really help if i did have that info)

Just off the top of my head, it could be anything from an issue with a bad 1.2 install, or even a known mod related bug, so a little more info would be nice for those who know all that stuff