on 26-06-2013 07:55
If you search the app store you will find some apps that block calls but I have to say that I don't know how good they are.
As I do some development testing for my work, I am running the new IOS 7 and that has a call blocker now, once you block a number they cannot call, txt, imessage or facetime you so as September is not too far away it might be worth waiting for the IOS 7 release.
fourqtwo (formerly cis01 until username became 'inactive')
on 27-06-2013 19:01
You cannot block numbers on a stock iphone.
However on a jail-broken unit their are tweaks such as iblacklist where you can.
If you dont want to j.b then in the upcoming iOS 7 it has been suggested they will include the facility to block calls.
If the caller is known to you ask them to stop or phone the police.
02 will change your number once for free.
Contact them here :