I found a couple more books that contain partial lyrics to SLEEP TALKIN' BLUES:

Mother of the Blues: A Study of Ma Rainey by Sandra R. Lieb (Amherst, Mass.: Univ. of Mass. Press, 1983), page 117.

and

The Message of Ma Rainey's Blues: A Biographical and Critical Study of America's First Woman Blues Singer by Sandra Robin Lieb (Thesis--Stanford University, 1976), page 141.

I think I have the whole song now:

SLEEP TALKIN' BLUES
Ma Rainey

1. You got a bad habit, daddy, talkin' in your sleep. (2x)
You talk so much some these nights, it should be worth one dollar a peep.

2. Do all your talkin' daddy, before you go to bed, (2x)
If you speak out of turn, your friends will hear of you being dead.

3. When you talk in your sleep, be sure your mama's not awake. (2x)
You call another woman's name, you'll think you wake up in a earthquake.

4. Do all your talking. Be careful as you can. (2x)
The insurance will bring in take for my man.

5. I warned you, daddy, nice as a mama could do, (2x)
You hear me talkin' to you: undertaker will be visiting you.