Exchange Unlock iOS7 cydia tweak allows you to kill exchanges requirement for a passcode lock.
When you turn on an Exchange email account, iPhone auto-locks the screen so that a password is needed every single time you slide the slider. That is pretty annoying. This tool gets rid of that, so that you don’t have to enter a password every time.
Note: this means that essentially this gets rid of password protection completely from your iphone springboard main screen. Use with care :)
Note: iOS7: you will have to enter your password once per respring. It should be stored after this. iOS7 version works much better. iOS7 users will not get encrypted email in any circumstances.