This week's giveaway is in the EJB and other Java EE Technologies forum. We're giving away four copies of EJB 3 in Action and have Debu Panda, Reza Rahman, Ryan Cuprak, and Michael Remijan on-line! See this thread for details.
On your way in you may have missed that JavaRanch has a policy on display names, and yours does not comply with it; specifically, a first name and a last name are required. Please adjust it accordingly, which you can do right here. Thanks for your prompt attention to this matter. [ August 02, 2006: Message edited by: Ulf Dittmer ]
Ping & DNS - updated with new look and Ping home screen widget
If you have access to the sources of the JDK tools, you could study the "jar" tool, which can update existing jar files. It might have some useful helper classes that augment the java.util.jar package in this regard.