This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
Do you mean deploy version 2 without shutting down version 1? I ask because you do not shut down the "server" (WebLogic Server) for a war deployment (although that seemed to work with an old WLS version, maybe 6 or 7).
For information about application versioning, see the documentation. You do not mention a version, so I am just including the first one that came up in my google search.