From onther forum
"Yes an Orange sim-locked Nokia N80 bought off auction sites can be unlocked by Orange without much hassle. The procedure is
1.) buy phone
2.) buy Orange sim (£1 online)
3.) register imei with sim by calling 08000790006
4.) wait for phone to activate
5.) call orange on 450
6.) Request unlock code
7.) upload £20 to prepaid balance
8.) Wait few days for code
I am waiting for my code so will update you once I have it and it has worked."
I received my unlock code from Orange this morning and it works. So to unlock a N80 on orange UK will cost you £21 (£20 for unlock,£1 for sim card).
My vodafone sim is working fine.
In the United Kingdom, government regulator OFCOM dictates that networks must release the unlocking information to customers for non-contract handsets (e.g. Pay as you go) on request. Consumers who purchase handsets under “Pay as you go” or a similar scheme are purchasing the handset outright at the point of sale, this has in effect made phone unlocking in the UK a consumer right.