husbands are allowed in the delivery room, but generally not in the labour ward as you may be in with other women. this is true of most (all?) public hospitals, including QMH. i heard that PoW are more restrictive than usual about when husbands can go into the delivery room, but generally they move you into the delivery room when you are in active labour (3cm dilated, i think..??). this is why i think labouring at home for as long as possible is a good idea. if you're nervous about when to go, you could get a doula (if not too expensive for you), who can be with you in the early stages if you wish, & can also advise when to go to hospital.
when i had my bub there in march, my husband & i were only separated for about 15 minutes while he did the admission stuff. i was 6cm when i arrived, so didn't go into the labour ward at all.
probably stating in your birth plan that you want your husband with you at all times would help, too. Also, they're usually responsive to a bit of firm, but polite insistence!