We have recently received email that indicates a sender
of unsolicited commercial email has used a forged return
address to suggest that it came from this domain,
quadrivio.com. Please note that we didn't send it! We are
trying to track them down to take appropriate action, but,
as it typical in such cases, there is a long series of
fraudulent registrations between the perpetrator and the
victim. Unfortunately, this is a frequent tactic of
spammers.
An excellent summary of the issues involved in this kind
of forgery can be found at the web site of another domain
that has encountered this problem:
www.obliquity.com/computer/spambait/idtheft.html