[VM] reply-all cc's myself, even though user-mail-address is set

[Tony's unattended mail]

I have this line in my vm configuration file:

  (setq user-mail-address "myu...@mydomain.com")

and yet when I reply-all, the email is addressed to myself - even when
I also have it configured to save sent messages.

How can I stop vm from including myself as a recipient?