[Samba] umount share on user logout

[Toni Casueps]

I have Windows and Linux clients accessing a Samba share. In the /etc/fstab 
file of the Linux clients I use the credentials=... option so that the 
system mounts the share when it boots.
If the only person that uses that PC is the one that I have set in 
/etc/fstab everything is ok, but not if it's another person because the 
permissions of the share are the ones of the first person.
Is there a way to do the same as the Windows clients? (i.e. disconnect share 
when one user logs out and ask for credentials either when the user logs in 
or when he accesses the share)