samba - Nov 2006 - Commands made by SAMBA when users log in and out...

Hello experts.
In our library there's a little "internet space" with 5 computers.
By now the computers are in a pear-to-pear network and to use the
computers, users must fill a form.
The idea is to create a database (MySQL maybe) and let the users log in
against that database. By now i've already read some documentation and i
know that this is possible.
My question is this:
Is it possible for me to configure what the samba reads and writes in
database when the users log in and out?
It is really important to know when the user log in (Date and Time) and
Log out (Date and time).
Samba must do something, every time a user logs in, and what i need is
to tell MySQL to write to another MySQL table by that time. The same
applies to the log off operation.
With these informations i could make statistical calculations that would
help people to analise the type of clients they have, among other things.
Can you help?
PS. I'm not worried about speed because as i said, this "internet
space"
will work with 5 PC's.


Best regards,
-- 

Jorge Ferreira