war manifest generation : optional=true not transitive

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:
<dependency>
<groupId>org.foo</groupId>
<artifactId>bar-jar1</artifactId>
<version>$

</version>
<optional>true</optional>
<!-- goes in manifest classpath, but not included in WEB-INF/lib -->
</dependency>

The problem is transitive dependencies of bar-jar1 are put in WEB-INF/lib.

For instance :
if artA declares
<dependency>
<artifactId>artB</artifactId>
<optional>true</optional>
</dependency>
and artB declares :
<dependency>
<artifactId>artC</artifactId>
<optional>false</optional>
</dependency>
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.