UPDATE: My fork of ADPassMon has now been merged with main & many changes have been made, for more information follow this link.
Over the past few Mac OS revisions, you’ve been able to alert users to impending password expiry. Shown below is this on 10.8:
Sadly, this no longer seems to work in 10.9. I’ve a bug logged with Apple (ID: 15339885) since 29/10/13 & as of yet this issue is still outstanding.
The change password box still appears on the day of expiry, but sadly doesn’t stop users from not able to login if their account expires over a weekend.