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A few days ago I took my IPhone 4S out of my pocket to find the lock button had somehow become jammed, with strong pressure it would activate but it was almost unusable, I have since sent it off to the repair center for repair.
I was wondering whether this was a common problem with this phone or not? I had the 3GS for 2 years previous to having this phone and never once had a problem with it.
Thanks for your post about the lock button being difficult to manoeuvre.
I've just has a search of this forum and can't find any other threads about this issue.
How old is the handset? If it's over 7 working days then I'm afraid you will need to submit it for repair.