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.
Right-click the project name, get properties, then go through it (I think it might be build path) until you find the Java version your project is using. It might not be the same as what you are using for everything else.