Just to clarify; It sounds like you once recieved a message and your name was in the BCC field. You'd now like to make sure that you can't see any names in the BCC field, and you want to know how to make that happen.
Is that correct?
The message you recieved with your name in the BCC field, was your name in any of the other fields (TO, CC)? Was that message an original or was it a reply or forward?
If you are using SMTP (thats most likely) then unless you take the convulated steps I mentioned in my earlier post, your names in the BCC field will not be displayed to anyone, including your BCC recipients.