From http://maven.apache.org/plugins/maven-war-plugin/examples/war-manifest-guide.html, war plugins distinguished the jars going to ear file and those going to WEB-INF/lib.
For a jar that's deployed on the ear and not in WEB-INF/ilb, you jus have to put scope=compile and optional=true:
<!-- goes in manifest classpath, but not included in WEB-INF/lib -->
The problem is transitive dependencies of bar-jar1 are put in WEB-INF/lib.
For instance :
if artA declares
and artB declares :
then artC is transitively included in artA dependencies but with optional=false.
IMHO it should be included with optional=true since artB is optional.
I'll attach a test case ASAP.