Does the iPhone relock if you put the same sim card in?

[samywamy10]

Hey all,
I'm going to hong kong on Thursday and in preparation I have had my phone unlocked by my carrier so I can use a cheap sim card there. I have two questions...

Because I am leaving on Thursday, I am going to put my original sim card back into my iPhone and change it on Thursday. Will the iPhone remain unlocked when I do this, or because I put the original sim back in willit relock to that carrier?

My second question is will a hong kong sim card work for my Australian iPhone?

Thanks!

 

[mrochester]

Once the phone is unlocked, it is unlocked forever. No amount of sim card changing will make it be locked again (and is the whole point of unlocking to begin with).