Unix Password File and smbpasswd file synchronisation?

[Charlie Grosvenor]

Hi
    Is there any way of keeping my unix password file and my smbpasswd file
in synchronisation? What i want to happen is when a user changes their
password under linux (passwd command) it changes their samba password as
well. When a user changes their password using samba it changes their
password in the unix password file as well, therefore the two should keep
synhronised. Is there any way of doing this? I am running redhat 7.2.

Thankyou

Charlie