Got error message when sending message to selected participants:
Cabability "moodle/course:trustcontent" was not found! This should be fixed in code.
Specific steps to duplicate: When to participants page in pogo course on test.moodle.org, selected two participants by checking box next to their name. In far-most drop down selected add/send message, and on subsequent page http://test.moodle.com/user/action_redir.php got the message.