Actually jboss-seam.jar is ejb beacuse it has same session beans. When I deploy my application as an archive everything works fine. When I remove jboss-seam definition from the application.xml then application works in exploded mode, too but then I have to change configuration for jboss-seam and this is not good. Obviously the problem is that for some reason, you cannot mix exploded and archived submodules in exploded deployment of an ear. This is my conclusion.
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