Weird Compile Issue

So I’ve been getting this odd error when I compile models now and then:

http://www.mediafire.com/convkey/d52d/ce2i3c12817g57k5g.jpg

Basically it turns the arms 90 degrees to the right for some reason but leaves the gun pointed forward. Not sure why it’s doing this but if anyone has an idea of how to fix it that’d be great.

That will happen when the skeletons have different origins. Try resetting the origins on the skeleton the arms are using.