Hi Tobias,
The canned replies do not currently have role permissions that can be assigned to them. You'll see that another community thread has been started for this feature request here:
http://portal.smartertools.com/community/a1411/canned-replies.aspx. If this is something you wish to see implemented I'd vote this thread up in order to gain visibility with our developers.
Andrea Free
SmarterTools Inc.
877-357-6278
www.smartertools.com