Import the Seam contactlist example, e.g. from https://github.com/seam2/jboss-seam/tree/Seam_2_3/examples/contactlist JBDS should show several EL Knowledge Base Problem warnings like "address" cannot be resolved , described in WFK2-219 In Project Explorer, select all projects related to the contactlist example and Delete Import the contactlist example again The EL Knowledge Base Problem warnings are not shown anymore