‘Lock Dock Bar’ places a set of default 4 apps on the lock screen of your iPhone, just above the slide to unlock tab. These are Phone, Mail, SMS and Calendar. Also present is the iPod control which shows on the top of the screen (not seen in the screenshot).
These apps cannot be rearranged or replaced as of now. But a good utility. Available free via Cydia.
Cydia is an Installer alternative, that Installs on Jailbroken iPhone 2.x… Info here
Image courtest iPhoneFreakz