Reveal Cydia Tweak allows you to view more text on notifications.
Check the video of the tweak in action after the break.
It allows you to scroll horizontally on banners and vertically on lock screen bubbles to read more of the message. You can also tap the lock screen table cells to expand the view.
Reveal jailbreak tweak is compatible with all iOS 5 devices and is available in Cydia under the BigBoss repo for @1.99.