Simple Mouth Rigging I'm having big problems rigging this characters mouth, it's really simple the mouth itself, and I want to do it with bones and not shapekeys.

The lips and the body are the same object.
Pretty much just start your bones at the edge of the mouth and work your way in, leaving a gap in the middle for size difference when the edges of the mouth move out.

I recommend using some sort of mouth animation reference sheet and choosing which shapes the mouth will be taking on most often, especially if your creature doesn't speak a human language where mouth movements are fairly non-caricatured and straight forward. This rigging system, however should do for a basis of most things, and with a little tweaking and weight-painting can be made much less scabby, however the immediate results aren't terrible :)

Obviously include more bones around areas that will need greater control over their deformation and do not forget about that gap in the middle of the lip.