/usr/share/irssi/scripts/autowhois.pl is in irssi-scripts 20131030.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38  | # /WHOIS all the users who send you a private message.
# v1.1 for irssi 0.7.98 by Timo Sirainen
use Irssi;
use vars qw($VERSION %IRSSI); 
$VERSION = "1.1";
%IRSSI = (
    authors	=> "Timo \'cras\' Sirainen",
    contact	=> "tss\@iki.fi",
    name	=> "autowhois",
    description	=> "/WHOIS all the users who send you a private message.",
    license	=> "Public Domain",
    url		=> "http://irssi.org/",
    changed	=> "2002-03-04T22:47+0100",
    changes	=> "v1.1: don't /WHOIS if query exists for the nick already"
);
# History:
#  v1.1: don't /WHOIS if query exists for the nick already
my $lastfrom, $lastquery;
sub msg_private_first {
  my ($server, $msg, $nick, $address) = @_;
  $lastquery = $server->query_find($nick);
}
sub msg_private {
  my ($server, $msg, $nick, $address) = @_;
  return if $lastquery || $lastfrom eq $nick;
  $lastfrom = $nick;
  $server->command("whois $nick");
}
Irssi::signal_add_first('message private', 'msg_private_first');
Irssi::signal_add('message private', 'msg_private');
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