Select the joint and go into component mode. To make things easier set all components to OFF. (So now you wont be able to selct ANYTHING) and then click on the little question mark sign. that will show you all of your joints rotational axis'. Pick the one you want to reverse. (IE flip180 degrees on the x asis) and type this in the command line:
rotate -r -os 180 0 0
remember to press enter on the number pad, NOT the keyboard. This should fix your problem.
Mike R
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