I'd tell him "We're going to have a baby, it's time to take an anger management class." Seriously. Parenthood, wonderful as it is, also adds stress to a couple's relationship. Make plans to head out to other support (like your family and friends or even your church) if he does not. You say "I need his support --" he is not the only place to turn. If he won't learn to get his temper under control, there should not be a helpless baby living under his roof, nor a mother of that baby to fight with him either.
It tends to take men longer to cope with the fact their going to be a daddy. He might just be having a hard time adjusting to the idea.. and I swear men get just as hormonal as we do. Is try not to stress momma maybe try talking to him about how hes been making you feel. Hell come around.. have you gotten a u/s yet? If not take him to the first one. That may help him get more excited about your lil one.