Lowest stamina in the game goes to mage's hands down.  I have a 70 lock, unbuffed with 5 pieces of epic gear from PvP I'm at 10,279 HP and have a little over 8k mana.  Once I get my full epic gear I'll have close to 13k total HP.  One of my friends that plays alerady has this.  13k HP and about 11k mana.  Warlocks own in PvP...unless it's against a maced rogue..lol  Stunlock is a pain.