Reversing Mecanim Animation

SuperSparkplug

Hi, so I have a model walking forward in Unity. Stupid me, I forgot to make an animation of him walking backwards as well. Actually getting an animation of that with my original file is proving difficult since the usual method of just reversing frames and adding them on doesn't seem to be working for some odd reason. Is there a way I can either tell Unity to reverse the walk forward animation when I press backwards (S) or make a reversed duplicate of the walk animation state?

Farfarer

Not used Mecanim, but in the legacy system, you can simply set the speed of the animation to a negative number. Can you do that with Mecanim?