Externpasscheck VoiceMailMain

Hi I am wondering is there away that I can update the users Voicemail password on our database and in the conf file at the same time?

I saw the option to run a script using externpasscheck but I am wanting to know the following.

Will the script attached to the externpasscheck send the username of the sip user or the sip number.

If there is any documentation on this that would be great.

As all my SIP accounts get stored in a database and then I have a perl script that makes the config files every 20minutes and reloads the core asterisk system.