In order to make it work I had to bundle the arquillian-jacoco dependency inside the ear/lib of the deployment under testing. It seems that the instrumentation is also made on the classes present in the ear/lib directory (i.e. seam-transaction). Is it possible to choose the classes that should be instrumented?
Hmm, the arquillian-jacoco lib should have been placed in ear/lib automatically.
Could you file a Jira on this, and add the @Deployment method you used as a illustration ?
I cannot reproduce the problem. I've added jacoco to all my sub projects and it seems to be ok now. I had the same problem this morning with hamcrest.... So I have the feeling that it is related to the fact that sometimes the arq-service does not undeploy properly leaving the following tests not bundled as they should.