That's probably due to the vast number of Java devs who have been doing it for many many years. Try Node.js, Rails, or Django; these are newer platforms where you won't have to compete with the same number-of-years-with-my-platform issue
I don't know where you are located, but have you considered applying to Dev BootCamp/App Academy/Hack Reactor or another such organization? From what I read they get their grads good jobs.
However I'm worried about what could euphemistically be called "cultural" issues. I'm a few years over 40, with a wife and kids, and all of the engineers at the company seem to be at least 10 years younger than I am. Being at the company's office gives me a distinct old guy at the club feeling.
I don't think the overall number of hours the team works is more than I could handle, but the team does a lot of young-single-guy-at-a-startup group activities (rent-a-limo-and-go-clubbing night, weekends in Tahoe, burning man, in-office happy hour) that I wouldn't want or be able to participate in; I need to be home with my family for dinner most nights and weekends and so on.
I'm wondering if anyone else has had the experience of working at a startup with, or as, an older programmer, and how it worked out?"
Two things every programmer should know (yes, this applies to you):
1) You are not smart enough to write your own crypto, so don't
2) You are not smart enough to write your own memory allocation, so don't