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.
You should not have to rewrite much if any of your application, but you may need to repackage some of your code. The idea is to encapsulate the functionality in service components, then they are deployed using the pipelines framework. Its really pretty easy to do, the reference framework and examples show you what is required -- and its intended to be very lightweight and flexible.