Virgin Mobile (Australia) Pty Ltd 0466 (Note: Virgin utilises the Optus mobile network,and as such,other mobile operators (Such as Exetel) may also receive numbers in this range)Student Administration Pty Ltd 0488 Currently unassigned 0426,04306-04309,0440-0446,045 (except 0450 and 0458),046 (except 0466),047,048 (except 0488),049 However mobile number portability means an individual number might have been " ported". There are also many resellers,and many companies buy "air time" from other companies for roaming.