I just had my car in yesterday to have this exact problem looked at. They could even reproduce it (lucky me!). But all they did was take apart the switch and put it back together and it started working for them.
Unfortunately, on my drive home from the dealer, it once again wasn't working for me. I don't have time to deal with it this or next week so I guess I just go without cruise control for a little while. Disappointed.
They did fix all my other woes though in this visit so I must say I'm quite happy otherwise.