Very close, except that you spelled "referrer" correctly, and HTTP doesn't. Fleshed out a bit more, this looks like 
#!/usr/bin/perl

if ( defined $ENV{'HTTP_REFERER'}
     and $ENV{'HTTP_REFERER'} =~ /dumdomain\.com/ ) {
    print "Location: http://www.anotherpage.com\n\n";
    exit(0);
}

print "Content-type: text/html\n\n";
...

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In reply to Re: Re: blocking naughty referrers by dws
in thread blocking naughty referrers by mishko

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