Idea plugin doesn't handle source zips correctly

If idea.module.downloadSources = true, and the source archive is a .zip file. Then the generated .iml file sets the url of the sources archive to a file:// url, and IntelliJ IDEA cannot read sources from it. In my opinion, the plugin should handle zip files the same way as jar files, with a jar:// prefix on the url, and !/ at the end.