override nobody@example.com

When using the mail () function to send an email to a linux server the header information shows two from addresses. (1)e-mail address that was defined in $from variable in the header. (2) nobody@example.com Can someone explain this? I only want the $from variable to show up in the header. Can I do this with the simple mail () function? Thanks Header info is below: From nobody@mars.com Mon Jan 14 08:33:19 2002 Return-Path: <nobody@mars.com> Received: from localhost.localdomain (localhost@example.com [204.65.32.5]) by pluto@example.com (8.9.3/8.9.3) with ESMTP id IAA12868 for <pluto@example.com>; Mon, 14 Jan 2002 08:33:19 -0600 Received: from mars@example.com (IDENT:root@mars@example.com [204.65 .32.11]) by localhost.localdomain (8.12.1/8.11.2) with ESMTP id g0EEXpOn001442 for <pluto@example.com>; Mon, 14 Jan 2002 08:33:51 -0600 Received: (from nobody@localhost) by mars@example.com (8.9.3/8.9.3) id IAA09861; Mon, 14 Jan 2002 08:35:08 -0600 Date: Mon, 14 Jan 2002 08:35:08 -0600 Message-Id: <200201141435.IAA09861@mars@example.com> To: pluto@example.com Subject: TESTING From: jb@example.com Reply-To: tm@example.com Mail () function below: $to = "pluto@example.com"; $subj = "TESTING"; $body="Begin101Test" . "\n" . $N . "\n" . $C . "\n" . $r . "\nEnd101"; $header="From: " . $email . "\r\nReply-To: tm@example.com"; mail ($to, $subj, $body, $header); __________________________________________________ Do You Yahoo!? Send FREE video emails in Yahoo! Mail! http://promo.yahoo.com/videomail/