Did you mirror them in blender? Look for "Show Normals" or similar in blender to see whether the faces actually show to the right side.
No offense meant dude, but please READ my post before pointing out the obvious: ...
Originally Posted By: achaziel
[...] (no matter whether it's fbx, obj or 3ds, and YES, I've checked every single mesh, face and vertice and their normals, they're perfectly fine in blender) [...]
