can any one help

no limit hold em flop down 3 players left in player 1 raises 1800 player 2 only has 2400 and goes all in player 3 calls the all in 2400 player 1 then wants to reraise to 3600 can he do this or is he just reraising his own bet as player 2 did not have enough chips to offically reraise but was intitled to see action ?

He can only re-raise if the all-in bet is more then half of the intial raise for you example all-in would have to be 2700 to be able to raise