[CentOS] Changing system users pass via webmin

Hi List,

I need my users to change their passwords, so I defined them as webmin users and gived them access only to the system/change password option to do so. So far so good... they changed their system passwords (in order to access email) but the change it's not reflected in samba passwords. I defined the option change password in other modules in webmin but it doesn't works, I also have in the smb.conf "unix password sync = yes" but the same. I will appreciate if somebody can give me an idea about how to ride this, or maybe using another app? o_0

Thanks in advance.

--Ivan.