Apple has introduced a handful of new features in iOS 4.3, second beta of which was seeded to developers almost a week back. One of these new features is the much desired return of iPad‘s hardware rotation lock switch. Though the feature is iPad exclusive, a workaround has been published by FSM to make this work on an iPhone 4. The process is quite simple, though a jailbroken iPhone 4 is required to make this work. Simply follow the easy steps given below to enable hardware rotation lock on your iPhone 4.
Download .plist files from here .
SSH into your iPhone and browse to /Applications/Preferences.app/ and backup general.plist and settings.plist. Now over-write them with the ones you just downloaded
Go to /var/mobile/library/preferences/ and edit com.apple.springboard.plist. Add SBUseSystemGestures as a key and set it as true.
Go to System/Library/CoreServices/SpringBoard.app/ and edit N90.plist. Add multitasking-gestures as a compatibility and set it to true.
Reboot. Now you can use your mute ON/OFF switcher on your iPhone as a rotation lock.