That white icon is because your icon cache has gotten corrupted. It's no biggie, just annoying. Usually, respringing the device works. You may have to respring more than once...
Or, you can get the free tweak from Cydia called iWipeCache. When you launch it, it'll automatically respring the iPad.
Or, for another way - my fellow moderator, f4780y, mentions that, for him, respringing from within the Springtomize 2 tweak works the best for getting rid of the white icons. It clears the cache better than any other respring tool, to include the one that comes with SBSettings.
that's the only fixes I can give. Generally, respringing the iPad works, whether you just plain respring it or use one of the two tweaks mentioned here. Guess it's "one of those things."
Marilyn
P.S. And, since this is about a jail broken device, I've taken the liberty of moving it over to the Hacking section. Thanks for your understanding.