In order to retrieve the e-mail headers for a message in Mac OS X Mail, you will need to:
1. Open the mail message in a new window by double clicking on it.
2. Click on View
3. Click on Message
4. Click on Raw Source
5. Copy the headers by right-clicking and choosing "Select All"
6. Right-click again to select "Copy"
You can now paste the header contents into a ticket response or chat window to receive additional assistance from Support.