Published plugins is missing modelVersion in POM file


We have just published a plugin to the portal for generating documentation via Enunciate.

But when I add it as a dependency, I get this warning about the POM:

Processing of …/enunciate-gradle-0.9.1.pom failed:
‘modelVersion’ is missing. in

Is this a bum in the POM generation, or an oversight in the plugin repository documentation (because I could not find anything about it).