Jammed lock button - what to do?

something sticky in it maybe?

 

It would be worth a shot to try to take it in. They often are lenient on the end date of the warranty, but not always. I had an iPhone 4 replaced for the same issue during the warranty period. It is a known problem, but not as common as some others.

 

Out-of-warranty repair is $149, so that's worst-case through Apple.

You can get the part from iFixIt.com and instructions for replacing the button yourself, but it looks pretty complex.

There are companies that will do it for you, here is one for $59.99 - I used this company for screen replacement and they did a great job:

http://www.ifixyouri.com/iphone-4-repair/268-iphone-4-power-button-repair.html

However you're without your phone for at least a couple days, plus shipping costs, so it's not necessarily THAT much cheaper than Apple Store (instant exchange for $149).

 

If it's been out of warranty for only a short while, if you take it to the Apple Store, you'll most likely be able to get it replaced for free as long as you're nice about it and your phone isn't broken in zillion places.

 

Can't you call before going in and making the drive? I wouldn't justify it as being an expensive repair at all. Worst comes to worst, you can replace the button yourself.

 

They would probably replace it during the warranty period. My friend's phone that I brought in wasn't in very good cosmetic shape in addition to the button being stuck, but they replaced it anyway. The employee said he had seen the problem before.
At the time I had it replaced there was a thread on here about the issue. A couple other people had gotten them replaced, and they had also been told that other people had the same issue.
I would definitely recommend taking it to a local Apple store. That same phone I got the back replaced free 3 weeks out of warranty after he dropped it.