had the same problem but solved it
I solved this as :
1.Made a call from my bros mobile .
2.then i clicked the end call button,then there will be small amount of time to go back to lock screen from call screen
3.in this time start clicking menu or home button on the phone.( better is to press end call and immediately start pressing home button,this will take to home scrren)
4.In your web browser from a computer change the password for your account.
5.make sure u have net connection for the mobile
6.now click the sync in mobile,and get back to lock screen and enter the new password
thats it u are in