Vista - Windows Mail BCC

I'm hoping this is the right forum for my question . .
I use BCC when mailing several people so that their email addresses aren't added to the recipient's address book for security (so that, if any of the pcs are infected with a virus that targets the address book these new addresses shouldn't receive the infection, hopefully).

This has been fine until today, when I forwarded a mail to several people and then found out it was a hoax. I tried to send out a correction mail but, when I looked at the mail I'd sent in the Sent folder there were no addresses in BCC. I tried forwarding the mail, just to see if the address list was somehow kept internally by Windows mail, but no it reported an error that there no recipients had been defined and so couldn't send the mail.

I've previously used Outlook and that keeps the details in BCC that you can see if you want to, but the recipients see "undisclosed recipients" or something, they don't see the other recipients details.

Can anyone tell me how one can see the BCC list of mails that have been sent, please?

TIA,
Trevor