Updating an Unlocked Jailbroken iPhone 3Gs to IOS6?

A bit complicated. I recently bought an unlocked jailbroken iPhone on eBay from a fairly credible source. It's 3Gs version 5.1.1 or something of that nature. Press me for more details if needed.

But the question is, I want to update it to IOS6. Now I know it has to be jailbroken, so if I de-jailbreak it or whatever and update it, will I lose the unlockability? Thanks in advance

Added (1). In response to the first person, I don't care to jailbreak it again. I never use it. But, is it possible to update it anyway?

Don't do it. There's no unlock or jailbreak option yet for iOS 6. Well, there's, but it's a tethered jailbreak. That means you have to connect the phone to your computer each time you restart the phone. Wait for the untethered jailbreak before you upgrade. Google "jailbreak iOS 6", and you'll get the info on when its available.

Check the base band version, setting, general, about phone, should be the last option. If it is 6.15 DO NOT update. Some of the older iPhones were unlocked using an exploit with that base band, referred to as the ipad base band, for an app through cydia to unlock it. If you try to update it with this base band you will fry your phone and it becomes a glorified paperweight.

Personally I would look up on google what the iphone 3Gs base band is for IOS 5.1.1, if you do not have the same one I would skip the upgrade. Chances are the unlocker used a variation of that method to achieve unlock, apple didn't do factory unlocking when the 3Gs was popular.

If you know for a fact it is factory unlocked then go ahead.

If you update jailbroken iphone then it will just update and will remove jailbreak.

If its factory unlocked, you can do whatever, if you don't want the jailbreak. Otherwise you will lose your unlock forever, if its software unlocked. Well, if its locked to AT&T, its better to have it factory unlocked, anyway.