3G[S] 3.1.2 Unlock then Jailbreak to iOS4 - will unlock persist?

[Foofad]

Question is as in my title - if I unlock my 3G[S] before I jailbreak it to iOS4, will my unlock persist? The reason I'm asking is because I will eventually be upgrading to the new iPhone and want to sell my 3G[S], and it'll sell a lot easier if it's unlocked. I won't upgrade to iOS4 if the unlock will... er, re-lock.

Advice?

Thanks guys.

[Simtech]

You have to re-jailbreak / re-unlock each time.

[Foofad]

Thanks for the reply. Would it be safer to just not bother jailbreaking until there is an unlock or is an unlock on the way? My SHSH is on file with Cydia so I can always roll back, correct?