When I create war that depends on other war, maven2 works ok, combining that two projects in one war. To do the same in eclipse, adding:
<wb-resource deploy-path="/" source-path="target/[module-name-version]"/>
to .settings/org.eclipse.wst.common.component eclipse file does at least that eclipse deploys all new jsp/resources from src path and all the rest from (previously generated by maven) target, that contains missing files from depended wars.
While it's a kind of work-around, it would be nice to have that as an option when creating eclipse files using eclipse:m2eclipse.