Don’t get declined calendar notifications in email

Using Outlook 2003 on WinXP – I have one user who does not receive a ‘declined’ meeting notification if a user first accepts, then declines a meeting request. The accept notification come in an email, but the decline does not. However, it does remove the meeting from the user’s calendar. I’ve looked to see if any rules are setup, but there are not. I’ve tested the same scenario on my machine and it works fine.
Any thoughts?