e-mail addresses from the pkg-descr file that could reasonably
be mistaken for maintainer contact information in order to avoid
confusion on the part of users looking for support. As a pleasant
side effect this also avoids confusion and/or frustration for people
who are no longer maintaining those ports.
but, the correct way is preserve original MASTER_SITE and add
freebsd.unixfreunde.de just as a backup, I'm doing it right now, restoring
original preserving the Martin's proposed backup.