How can I tell whether my iPhone 3GS is simlocked?

[MBPMax]

This might be a stupid question, but basically the logic board of my O2 (UK)-locked iPhone 3GS failed back in August and this iPhone repair shop replaced it. It seemed to be a used logic board since some data from the person who used to own it was still on there, but it was relatively cheap (150 EUR) and everything worked fine, so I didn't care. I received the phone jailbroken and was told that its baseband (05.16.02) was unlockable. Now that iOS 5 has come out, I was considering updating it, but obviously I don't want to lose the ability to unlock the phone since it's the only one I have that works in the UK. By coincidence I checked Cydia at one point and it turns out that ultrasn0w is not installed. I then also realized that the baseband I have is not unlockable by ultrasn0w anyway.

So I'm now assuming that the shop either came across a logic board that is simlocked to the O2-UK network or that the logic board does not bear a simlock at all. Is this correct or am I missing something here? And is there a way to check whether the iPhone is simlocked using its serial number?

And on a slightly unrelated note - how can I tell which SHSH blobs have been saved? Is it just the first line in Cydia saying "SHSH: iOS 4.1, 4.3.3, 4.3.5"?

 

[nebo1ss]

Put a different SIM in it and you will soon find out if it is SIM locked. The SHSH blobs that show on Cydia are the only ones you have.

If you have an O2 phone it is easy to get it unlocked. If you on pay and go for Sterling 15 they will unlock it. If you on contract they will unlock it for free.
Just go to the O2 web site and fill in the form. I am assuming that you are in the UK.

 

[MBPMax]

Thanks! I figured it was either simlocked to O2 or does not have a simlock at all. Either way, I upgraded to iOS 5 (while preserving the baseband) and jailbroke it using the latest redsn0w build. Everything seems to work fine, but there's one thing I don't understand - this jailbreak is meant to be tethered, but I managed to turn the phone off and back on without having to start up redsn0w at all. Is there an explanation for this or do I simply not understand what a tethered JB is?

 

[nebo1ss]

Thanks! I figured it was either simlocked to O2 or does not have a simlock at all. Either way, I upgraded to iOS 5 (while preserving the baseband) and jailbroke it using the latest redsn0w build. Everything seems to work fine, but there's one thing I don't understand - this jailbreak is meant to be tethered, but I managed to turn the phone off and back on without having to start up redsn0w at all. Is there an explanation for this or do I simply not understand what a tethered JB is?

That means you have an old boot rom 3GS. They are the only ones that are untethered with IOS5 presently.

 

[MBPMax]

That means you have an old boot rom 3GS. They are the only ones that are untethered with IOS5 presently.

Oh, that's great, given that my previous logic board had a new bootrom Thanks!