Can't uninstall a plugin from ajenti

Hi everyone, i've got two dedicated server with two different ajenti instances. about 1 our ago i've installed a community plugin from the web interface, after i've restarted the panel for the new plugin ajenti on all two istances went down and now (being that i did the automatic installation) i can't remove that plugin because i'm only with ubuntu shell or sftp connection.

if someone can please tell me where i can find the plugin directory with the full-automatic installation i will be very happy :))

Thanks at all!