What to do about my boyfriend's overprotective mother?

My boyfriend and I have been dating for 6 months now and we are both 17 years old. I think that is definitely a fair age to be dating. The problem is his mother is WAY to overprotective. We are constantly babysat by his 9 year old sister, at all times. I had my permit for 11 months and I’ve had my license for 6. I’ve never been in an accident and my parents think I’m a wonderful driver…but his parents won’t let me drive him until I get my Senior license, which I can’t until next August, though his stupid friends who race each other are allowed to drive him. He also isn’t even allowed to have a cell phone, so our communication is awful and we barely talk. I feel like I’m 12 again. I love him to pieces though, I can’t just walk away. What can I do? PLEASE help. Answers from Mothers would be appreciated. My parents aren’t the type to allow their kids to have sex, but they realize we need freedom and they’re totally cool with us having that. His on the other hand…:/