The war should be deployed inside the ear in this situation.
Seam finds all seam components in jars on the classpath. The only two requirements are that you need to have an - empty/configured - seam.properties file in the root of the jar and the beans configured for Seam-interception (@Name annotation and definition of Seam interceptor on bean or in ejb-jar.xml).
In our configuration (JBoss 5.1 and Seam 2.1.2 ) this works without a problem. However be aware that only the
WAR-projectcontains Seam, so you can't upgrade the EJB's without
restartingthe application or the server.