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.
This is more complicated than it might seem. You have to allow for the case where you're at the end of the list and there is no next object. I can't think of a way to make this work with <logic:xxx> tags. Even if you figured out a way, you'd end up having to use some scriptlets anyway.
If I were you, I'd just write a scriptlet to handle this. Another possibility would be to write your own custom tag.