Md3 problems

Sometimes(heck,almost always) when i export models(which look just ok in other formats) to md3 (quick3d,but tried milkshape) the geometry is totally uh,should i say fu***d..im not sure what to make of it,a friend said that could be scale problems-the model is too big or too small,but hasnt fixed the problem..? Anyone has any other ideas?

Any help is welcome.