I have searched the internet back and forwards looking for a problem I had with a mesh that I have and I was getting now where fast. I wanted to use an animation clip that I created with one character and use it on another character. Seems simple enough right? But the problem was that even though both meshes are in the standard T pose, I made a slight error in the construction of the skeleton of one of the characters. Instead of making a new skeleton for him, I copied the skeleton of one mesh and moved the joints into position of the new mesh that I'm having problems with now. The mesh works fine but the joints rotation is not zero. So if I character map the two characters, the animation would not be the same. I looked for ways to set the rotation of the joints to zero while leaving the joints where they are, but the only solutions that I found was an out dated plug-in for Maya 7 and 8.5 that says I have to rewrite it for my version of maya, and a forum that said to detach the mesh from the skeleton and freeze the joints rotation back to zero and re bind the mesh.
First, I don't know how to write a plug-in yet, and my character has a lot of different meshes that make up the character and that would be a long process to do. So I accidentally ran into this nice little solution. Just to let you know, this technique does not really set the joints to zero but it is a good work around.
Ok, if you look at my character you can see it is not so much in the T pose as it is in the creation of man pose. When I select the left shoulder joint you can see that the X, Y and Z rotation is not zero. Don't worry about these channels being highlighted, I just have key frames set for those channels.

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