BCC (Blind Carbon Copy) by definition is blind. The header should never be created by a mail client because the message should not display that it was sent to anyone in the BCC field.
An email client submits BCC mail in the SMTP envelope information. Mail servers pass the message along via SMTP and the delivery information is kept in tact. There is no BCC information in the message headers even before it goes out to the Internet for delivery.
One potential downside to using DomainPOP in MDaemon is when mail is addressed via BCC. When MDaemon downloads the message via DomainPOP, the SMTP delivery information no longer exists. MDaemon has to make the best guess as to where the message should go when parsing the headers.
Some ISPs stamp a header so that the SMTP delivery information is available for parsing, but it's not required. These headers may be “Envelope-To” or “Delivered-To” or something similar. Your ISP may be able to do something along these lines. Alternatively you could ask them if you could receive mail via ATRN instead of POP because then the SMTP envelope is still there.