There used to be multiple tweaks to add settings for calibrate touchscreen finger projection in ios 1.x-3.x, they all targeted the "SBFingerProjection" key in com.apple.SpringBoard.plist previously. But this key seems not working in ios4.

Most iDevices have several mm "dead strips" at the bottom of the touchscreen, you can test this on drawing apps like brushes. This makes the activation of "slide from bottom" in activator very hard to trigger. But with the previous tweaks, it was fixed flawlessly. Is there any hacks to address this problem?