bleeding brakes problem!?

[desolate]

I'm in the process of bleeding my brakes. I have started on the rear right, the first caliper. Anyway the air bubbles never end. I've gone through 2 32oz bottles and the bubbles are never ending they never stop coming out. What is going on here? I also hear a hiss by the master cylinder. It's coming out of the line that goes into the intake mani for vaccum. Am I doing something wrong here?!