HANKO  Thank you for sharing this---I never would'a guessed. And it blows my mind that you got back to us just about 10 minutes after my post---and I thought it was probably a "dead" string.

God bless you, Bill! --Hanko  
(Version 2.0.0.16)

HANKO  A temporary workaround for me has been to go back to Netscape 7.2 (from which I recentlytransferred into Thunderbird 2.0.0.16 because this version is finally able to import all my mail files & address books), and send emails from Netscape with the desired Bcc tags.

Really sucks, but until a BCC extension is available for Macs, I'm stuck with it.  
(Version 2.0.0.16)