domain isn't registred, but does exist in root-servers?

[diederik () dmclf org]

just wondering about the following:

there is no whois-info for sedgq.com
(response: No match for "SEDGQ.COM".)

but, host sedgq.com
sedgq.com has address 66.218.79.155
sedgq.com has address 66.218.79.147
sedgq.com has address 66.218.79.148
sedgq.com has address 66.218.79.149

how can this be?
i mean, afaik a domein needs to be registred before its 'known'

this because of an email i received like:
----
Received: from [66.179.231.27] (helo=ims-2.prv.ampira.com)
    by dmclf.com with esmtp (Exim 4.31)
    id 1CLSdk-0002yb-2c
    for dmclf () dmclf com; Sat, 23 Oct 2004 22:37:28 +0200
Received: from cws-3.ampira.com ([66.179.231.35] 
helo=cws-3.prv.ampira.com)
    by ims-2.prv.ampira.com with esmtp (Exim 4.24)
    id 1CLSdc-0002q2-8O
    for dmclf () dmclf com; Sat, 23 Oct 2004 16:37:20 -0400
Received: (from www@localhost)
    by cws-3.prv.ampira.com (8.11.7p1+Sun/8.11.7) id i9NKbGF19224;
    Sat, 23 Oct 2004 16:37:16 -0400 (EDT)
Date: Sat, 23 Oct 2004 16:37:16 -0400 (EDT)
From: auto-confirm () amazon com
To: dmclf () dmclf com
Subject: Amazon Security Request

Dear Amazon User,

During our regular update and verification of the accounts, we could not
verify your current information. Either your information has changed or it
is incomplete.
As a result, your access to buy on Amazon has been restricted. To continue
using your Amazon account again, please update and verify your information
by clicking the link below :


http://www.amazon.com () sedgq com/exec/obidos/subst/home/?EnterConfirm&UsingSS
L=0&pUserId=&us=445&ap=0&dz=1&Lis=10&ref=br_bx_c_2_2


Thank you very much for your cooperation!

Amazon Customer Support
Please note: This e-mail message was sent from a notification-only address
that cannot accept incoming e-mail. Please do not reply to this message.

Thanks again for shopping with us.

Amazon.com
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