Unlocked iphone (1.1.4) works with one SIM card but not another

[autolysis]

hi guys

i've a 1.1.2 OTB 8 GB (AT&T) iphone that's upgraded and unlocked with various pieces of software (ziphone, iliberty and winpwn) to 1.1.4

it works with a SIM card from a Singapore carrier (Starhub) but when I insert an O2 Pay-as-You-Go (basically a prepaid SIM card), it says No SIM card installed no matter what I do. I tried all those unlocking software and it's jailbroken but just won't recognize the SIM card.

If I re-insert the Singapore SIM card, it recognizes and works. Also, if I put the O2 SIM card to a Nokia phone, it works too. Just won't work when I insert the O2 SIM card into the iphone. Any help is greatly appreciated!

[autolysis]

no one? is anyone here using an unlocked iphone with O2 pay-as-you-go in UK? I know O2 is the exclusive carrier for iphone in UK but that's for plans with contract i suppose?

[Poseidon79]

I would try 3 or 4 different SIM cards so you can see if it's a bad SIM or what...

[autolysis]

I would try 3 or 4 different SIM cards so you can see if it's a bad SIM or what...

thanks but like i said in the first post, I did put the O2 SIM card into a Nokia phone and it worked fine. so that should rule out bad SIM card?