Call aviation australia and clarify your particular case to them and they'll give you clear guidlines on how to get your CASA license after having served in the ADF and the dispensation you get in the experience requirment.
However it's more advisable to look into taking the EASA license instead since both CASA and EASA are supposed to merge in the future and the EASA license is recognized in australia as well as almost worldwide whilst CASA is only recognized in australia (hence jobs prospects are only limited to australia) and most CASA licensed people are looking into converting to EASA already.
By the way if you're still in the ADF stay put untill you find a job as a fitter in one of the airlines then think about doing the EASA or CASA modules once having secured a job already since jobs are scarce nowadays..
Good luck
Last edited by flame_bringer; 18th Jun 2012 at 11:41.