Never Mind, found it online, Someone else had the same problem. Here is the fix they quoted and it worked for me.
"In my case, I installed my own certificate which even on removing was some where present don't know where so ultimately I cleared up every thing and again tried to remove pin and it got removed.
Proper way would be settings-->security-->clear credential Clear credentials is last option under security heading.
And now u can change your pin setting-->security-->screen lock-->swipe/none whatever you feel comfortable with."
Thanks to this guy for solving my problem.
12-26-2013 07:19 PM