global_taboo_headers seems not work

[bferi @ tbsz . sulinet . hu]

Hi!
First, sorry for my english.
I will us global_taboo_headers for filtering the incoming messages to my
lists. For example, sender@subdomain.dom and all senders from that domain.
In the majordomo.cf file I wrote:
$global_taboo_headers = <<'END';
/^from:.*\@subdomain\.dom/i
END
Majordomo seems not bouncing the message, it sends out to the lists.
Why? Ani ideas?
(ooops. Any!)
Please, send reply to my address too, I'm not subscribed.
TFA!
                Ferenc Bajan
               bferi@tbsz.sulinet.hu