I posted this up in the Max forum, but I figured it couldn’t hurt to drop it here, too.
I ran into this problem after modelling a quickie character in Wings to test out some rigging in MAX to then be brought into MotionBuilder. Big problem, though, is that I mirrored the left arm chain and leg chain in order to create the right arm and leg, and I hadn’t realized that the mirror process simply set the scale of the parent bone to -100%. Kind of lame, now that I’ve gone to all the trouble of painstakingly skinning the bastard.
Now, bearing in mind that I’ve gone through the documentation and tutorials, as well as done some rudimentary searches online, I can’t for the life of me figure out whether or not it is possible to reset the scaling to a positive value of 100%, while keeping the bone chain in the same position. The closest analogy I can think of is the “Transform Permanently” (or something) command in UnrealEd, which simply zeroes out all transformation values while keeping the new position.
(The MB VTMs mentioned this problem, but only gave a solution for Maya users in the form of a MEL command)