We are seeing sporadic reports of faculty being unable to set grade exceptions within Gradebook.
Faculty do the following:
1. Go to the Gradebook for a course.
2. Select the "Grade Exceptions" tab.
3. This generates the error "Sorry, but you do not currently have permissions to do that (Manage grades)"
Admins do not see this error.
This bug may be associated with another Gradebook error we're seeing, in which an "invalid context creation" error is thrown by Moodle when viewing the Gradebook with debugging set to "developer".
That said, we are seeing this problem on courses that do not have the above error. The users in question are part of the "teacher" role, which does have the "manage gradebooks" permission within Moodle 1.7.