you can take a look there: JIRA-2371 if you need a simple example.
I used the testproject-master-JBSEAM project to know what my multi-modules project should look like (boostrap folder, classpath,...) in order to run integration tests with maven, testng and jboss embedded.
Even though the example is a few months old, it should be quite helpful for you (i know it was for me). Don't forget to update the jboss-embedded dependencies versions though.
Hope it helps you...
Will it work under Eclipse+WTP/JBossTools (that is with m2eclipse or maven-eclipse-plugin) without manual configuration...?
I've heard/read some of Seam dev's already solved all the problems, I hope the result will be published soon...
Update: I have elaborated the setup of Testing in Seam with Maven in the below link. Also you have code coverage report by Cobetura.