Mirror pose using specified axis as reference point.

Hi,

I am a bit new to blender, so I don't know if this already existed. If it doesn't, I believe it is a fantastic idea that would come in handy when the character is no longer at the centre of the grid.

I noticed the mirror pose (Ctrl+Shift+V) uses the global axis as it's reference point. What if we could specify the axis, like for example pick the torso and use it's local axis as reference to mirror pose.

Thanks