Another 747-400 came to Iran.It's first flight was on 12/04/1993 and dellivered to United Airlines on 22/04/1993.Mahan Air knew the sanction and bought it from United Airlines via Blue Sky and changed the registration number to G-CEFF.It was stored at AMS and finally came to Iran for Mahan Air with registration number EK-74779 ! note 2 last numbers at the end of these EK registrations.... It's 2 last numbers of that aircraft msn number ! for example for this aircraft; msn or cn is:26879/973
you can see 3 shots of this bird in this iranian website :

http://www.iraviation.com/Picture/list.aspx?&RegisterID=473

This 744 was working for Mahan Air in international routes like Bangkok,after few months It was operated by Iran Air for hadj flights.But now It came back to Mahan Air.But the other one EK-74783 still operated by Iran Air.