note:"you need to backup ur content in order to save them if something goes wrong!!"
1st things first you need to jailbreak your idevice
go to settings and general and then save your current mac adress.
now download these tweaks from cydia
now go to terminal and enter the following commands
enter alpine as password if you didnt change it
now use the command to spoof the mac id
where xx:xx:xx:xx:xx:xx is the mac address you want to spoof to!
restart your idevice and reactivate it
voilla your device mac id will be changed which you can check that under settings general about!!
warning:"do not spoof your mac address as 00:00:00:00:00:00"
as it will disable your idevices wifi driver and u will have an hefty shit job to recover that!!