[luau] user management programs?

[Joel]

Does anyone know of any user account managment tool that can be configured to 
be run by a non-root user (specifically, a lab manager)?

I'm looking for something with a light-weight GUI or web-based interface, so 
that the non-technical lab manager can take payments, create new accounts 
(that expire after a certain time period), extend the epiration date (upon 
getting a new payment), and other such tasks.

It would be even better if it also included read-only access to user logs, as 
well, so the lab manager could check things like login times, duration 
online, and so on. 

kuser, linuxconf, userdrake, and webmin aren't really set up for this. Any 
existing software you know about that would be?

--Joel