I'm so glad you asked. I was about to post a similar question.
I have been dealing with frozen shoulders for about 18 months. It started with my left shoulder and I'm not really sure which came first, the frozen shoulder or the torn rotator cuff, but I had surgery back in 2007 to repair. My shoulder became horribly frozen post surgery and I ended up having it manipulated under anesthesia. I still have to arrange pillows under it to sleep at night. My Ortho surgeon suggested I sleep in a recliner....forever! I'm just not willing to do that.
About a year after the left shoulder issue, I started experiencing pain in my right shoulder. I had a torn labrum and it was partially frozen. After surgery, it became completely frozen and I had a manipulation on the right shoulder in Nov '08.
So, both my shoulders are still painful, somewhat frozen, and very weak. My massage therapist calls it 'Diabetic shoulder' and has several Diabetic clients suffering from the same issue. I find that deep tissue massage helps along with PT. I do not recommend having the manipulation done unless you are not progressing with PT. I'm also considering trying acupuncture to see if that provides any additional relief.