Exchange Notification (Delay) Deleted user

I have a user lets say user (A) that sends user (B) a meeting request via Outlook 2003. I then get a message back, via e-mail instructing me of an Exchange Notification delay to User (C)
Why do i get a notification from user (C) when he was not invited to the meeting?

User (C) was a recently deleted account. When i look in Exchange system manager the account has a red cross against it. If i purge this accoutn will i stop getting these messages

To: Test, Test
Subject: Delivery Status Notification (Delay)
This is an automatically generated Delivery Status Notification.

THIS IS A WARNING MESSAGE ONLY.

YOU DO NOT NEED TO RESEND YOUR MESSAGE.

Delivery to the following recipients has been delayed.