The relevant error above is probably this one: java.lang.NullPointerException | at org.jboss.tools.seam.internal.core.scanner.java.ASTVisitorImpl.visit(ASTVisitorImpl.java:90) | at org.eclipse.jdt.core.dom.SingleMemberAnnotation.accept0(SingleMemberAnnotation.java:161) | at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:2478) | at org.eclipse.jdt.core.dom.ASTNode.acceptChildren(ASTNode.java:2548) | at org.eclipse.jdt.core.dom.AnnotationTypeDeclaration.accept0(AnnotationTypeDeclaration.java:239) | at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:2478) | at org.eclipse.jdt.core.dom.ASTNode.acceptChildren(ASTNode.java:2548) | at org.eclipse.jdt.core.dom.CompilationUnit.accept0(CompilationUnit.java:214) | at org.eclipse.jdt.core.dom.ASTNode.accept(ASTNode.java:2478) | at org.jboss.tools.seam.ui.text.java.scanner.JavaAnnotationScanner$ASTRequestorImpl.acceptAST(JavaA | nnotationScanner.java:187) which I'm guessing is one of the Seam editors. Is that correct? How large is your XHTML file? If you can attach the whole XHTML file, it would help in trying to reproduce this problem. If the editor you're using is one provided in Eclipse (ie., same behaviour when using the Eclipse 3.4.2 Ganymede JEE bundle without any JBoss Tools installed in it), then this is a bug for the Web Tools project. https://bugs.eclipse.org/bugs/enter_bug.cgi?product=Web%20Tools&compo... View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4216831#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...