How to crack many WPA2 passwords at the same time?

Hi.

I'm using oclHashcat. I have three passwords for three different WPA2 networks. I was trying to combine them so that oclHashcat can try to crack all of them at the same time, but it doesn't seem to be working. It only picks up the first password in the list and tries to crack it. So it seems that I need to crack each password separately. Is there any way to speed up the cracking of WPA2 passwords and crack them in parallel?

Thanks.