pam.password.expiry.warn.mesg
This configuration parameter specifies the text displayed by a PAM-enabled application to warn the user that her password will expire in pam.password.expiry.warn days or less.
When the message is displayed, the '%d' token is replaced with the number of days until expiration. The message must contain exactly one '%d' token and no other '%' characters.
For example:
pam.password.expiry.warn.mesg: Password will expire in %d days