t looks like the most recent Moodle upgrade 1.7.1 has a problem with the glossary. It seems as though students cannot edit their own entries in the shared work database any more. That makes it quite a pain for students to maintain their entries, as they have to delete old entries and then create new ones rather than modifying existing entries.
I checked the settings, and "edit always" is selected, which should give students editing privileges. When they try to edit, they are told that they don't have permission to make changes.