As you know PDF Report Plugin is at same time a Maven plugin and a Sonar plugin, so actually his packaging is maven-plugin and it can't be changed. Currently I only know one solution, write separate plugins, one for Maven (called as post job action) and other for Sonar, containing all Sonar related classes and configuration.
Do you know another option?
sonar-plugin packaging needed to create correct metadata for your plugin, in it's turn those metadata required for update center. Of course you can add them manually, but for me it sounds like a hack, which may lead to problems. So my suggestion is to create separate plugins.
Also note that your plugin should have key "pdfreport", since this key was reserved for you in update center.
Ok. I will divide the plugin in two, Sonar and Maven plugin.
Thanks for the reserve
I see that you closed this issue - congratulations!
But since you made significant changes in plugin, could you please request vote/review before release ?
Of course. I'm waiting for a reply in http://jira.codehaus.org/browse/SONARPLUGINS-456. If there is no reply then I will mark it as invalid and will call for review.