Storing Tweener in variables

hey can someone help with this… im trying to store a Tweener animation in a variable like this…

var mycamtween:Tweener.addTween(camera, {zoom: 4, time: 1} );

however this doesnt work i get…

1046: Type was not found or was not a compile-time constant: .

Try this:

var mycamtween:Tweener = Tweener.addTween(camera, {zoom: 4, time: 1});