Ladies and Gentlemen, as discussed with Max and Fred on IRC, there are projects using Java 6 API but still having Bundle-RequiredExecutionEnvironment: J2SE-1.5 in their MANIFEST.MF's. The projects in question are the following: * org.jboss.ide.eclipse.as.ui using java.util.Deque * org.jboss.tools.seam.ui using java.lang.String.isEmpty() * org.jboss.tools.maven.ui using java.lang.String.isEmpty() org.jboss.tools.seam.ui and org.jboss.tools.maven.ui can be fixed either though (a) replacing isEmpty() with lenght() == 0 or through (b) changing the execution environment to JavaSE-1.6 org.jboss.ide.eclipse.as.ui can be quickly be fixed only using (b). Best, Peter