Approved I-140 to J2

[agh]

I am currently on H1B status with an approved I-140 petition. My wife goes into J1 status starting Aug 2012, halfway across the country. Seeing the manner in which priority dates are expected to move, I'd think it will probably be 2-3 years before my date becomes current.

Given this scenario, in the case of a layoff and being unable to find another job, is it possible for me to apply for J2 status based on her J1? I know I have shown immigration intent by filing I-140 and I can ask my employer to revoke it. We really do not intend to live separately and we think GC is not worth it.