countdown timer implementation in UILabel?

I am Implementing a countdown time开发者_Go百科r in my app. In the functionality, I need to display the remaining time before Jan 1st 2011. In months, days, hours and minutes format. Can any one please help. Thanks in advance.

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use an NSTimer which update you're label everytime it's fired

http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSTimer_Class/Reference/NSTimer.html