[Asterisk-Users] Password in VoiceMail

[Béasse Christophe]

Hi,

In voicemail. i  declare  :

1000 => 1234, xxxx yyyy,tintin at milou.com

I don't see what's password 1234 is for  ?  
password for what ?
Where this password is used ?
Where this password is defined ?

Thanks

Chistophe