Add CheckPluginVersions.groovy script from http://gist.github.com/130031 to Grails . Introduced in this blog article http://adhockery.blogspot.com/2009/06/checking-for-plugin-updates.html .
If you're anything like me you probably like to keep all your Grails plugins updated to the latest versions. It's quite easy to miss a release announcement and not realise there's a new version available. Although grails list-plugins will list out the available versions and what version you currently have installed it doesn't really highlight the plugins you could upgrade. I threw this script together this morning to do exactly that. It will simply check the plugin versions you have installed against all configured repositories and notify you of any that could be updated.
Copyright Robert Fletcher. He would have to release this under Apache license in order to include in to Grails ?