Hi Elayne,
My sister is in that same exact process now - do it while he is incarcerated - please! My sister's attorney didn't do it fast enough, he got out, is contesting her divorce, and now things are horrible - he is constantly harassing her, and getting her on stupid grounds, such as adultery, and crap like that.
My opinion would be to get to your attorney, and have him draw up papers now while he's behind bars before it's too late. He will have a harder time I think trying to contest the divorce, since he won't be out and about getting wild and crazy ideas, just trying to make your life crazy.
Check with your lawyer. Good luck.