Dynamic Groups or Status Text

I think I need some hints on how to do this if it is possible.

Our managers would like a plugin that can read from a database and change the status text or create a dynmaic group showing which users are out sick or on vacation. Reading the data isn’'t the problem for me… it is updating the contact list to show which individuals are out.

Is there a way to create a group that shows a list of people (even if they are offline)? Which “managers” would I need to use to create a group and populate it? I guess I could have the admin create a permanent group, but I would still need to update the members dynamically.

If I cannot populate groups, can I display additional text next to contacts (even if offline)?

Worst case I’'ll just have to add another tab that shows the list, but it would be nice to see it in the contact list directly…