There was nothing special with maven-war-plugin execution, it was just declared, no special configuration, just plain default execution.
I'm not sure, but as far as I can remember there were no quickfixes available, nothing special/related was in logs, and plugin was installed. Will try again.
Btw, here is link to this broken eclipse bundle/installation: http://dl.dropbox.com/u/11530426/eclipse-3.7-SR2-Full--broken.zip (~600MB)