Should white/blacklists work on host-only domains?

[Chris Blaise <cb...@esoft.com>]

	We have some systems that, admittedly incorrectly, send us
messages with host-only domains like:

 From: somereport@somehost

	Sometimes these messages are flagged as spam and I'd really
rather just whitelist them.  However it doesn't work.

	I've worked it down to the routine that extracts addresses from
header lines, find_all_addrs_in_line in SpamAssassin.pm.  The regex it
uses to determine an email address is:

 $line =~ s/(?:mailto:)?\s*
          ($ID_PATTERN \@
          $HOST_PATTERN(?:\.$HOST_PATTERN)+)//oix

	Now, I can "fix" the problem by changing the "+" to a "*" to
change the behavior of matching the domain, but can anyone think of a
reason why this would be bad?  This fixes my immediate problem, but I'd
want to make sure I wasn't breaking something else.

 Thanks,
 Chris