Outlook calendar delegate doesn't receive neither meeting acceptances nor read receipts

Environment:
Single Exchange 2007 mailbox server and both PCs with Outlook 2003 SP2.

Scenario and requirements:
Typical executive / secretary relationship where the secretary requirement is to help the executive manage his calendar. Secretary should be able to create, edit, delete calendar appointments. Secretary's Outlook tracks messages for all items sent. I have shared the executive's calendar and made the secretary a delegate of his calendar. Secretary is able to create, edit, delete calendar appointments on executive shared calendar from her Outlook client.

Problem:
When a recipient accepts a calendar invite created by the secretary on the executive's calendar, the calendar acceptance and read receipt go to the executive's Inbox instead of the secretary's Inbox.

Goal:
When the secretary creates a calendar appointment on the executive's calendar, the calendar acceptance and read receipt should go to the secretary's Inbox. When the executive creates a calendar appointment on his own calendar, the calendar acceptance should go to his own Inbox.

What permissions am I missing? I would've thought that the delegate permission model would've taken care of this...however, when I think about it...the owner of the mailbox and thus the calendar is the executive...so it makes sense that calendar acceptances go back to the executive's Inbox...is it even possible to accomplish what I'm describing? I'd appreciate your assistance...thanks.