Env Var expansion in procmail filters?

    I'm trying to make my .procmailrc at least partly generic,
so that it can be used by other people with minor changes.  E.g.
I use $DEFAULT instead of /var/mail/waltdnes.  Can I use

"* !^(To|Cc|Bcc):.*$LOGNAME" instead of "* !^(To|Cc|Bcc):.*waltdnes"

    I know that comments aren't allowed in the middle of a
multi-condition filter, so I want to check here, rather than
finding out "the hard way" that it doesn't work.

 Walter Dnes
 <waltdnes(_at_)interlog(_dot_)com>