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It is sufficient to use standard utilities such as 'passwd', the password will be updated in the MySQL database as well. Tested with 'passwd' and User Accounts applet in GNOME'@@@1'See the 'pam_to_mysql_update.sh' section in the 'Overview' page for utilities with which this has been tested. In case prompted with "Current password:" (exactly as written here) it is sufficient to ignore and press enter. Commands that expire or disable a user's system user account (or password) without deleting it (such as passwd -l) will not cause the credentials in the MySQL database to be disabled, thus it is necessary to take care (perhaps with a site specific lock user script) to also invalidate the same.
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