MrLock is a great utility that will change the way you lock your mobile phone. Available for symbian 3rd edition phones only. Some of the things you can do with MrLock :

• You can set the idle period after which Mr Lock will autolock the keypad.
• You can also define the profiles in which Mr Lock will be enabled.
• And last but not least, you can ask him not to lock the keypad when you are running a particular application.