Description:
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Hello,

I have a problem with the mail() function. The OS is Windows 2000 Server SP4 + IIS 5.0 + MySQL + PHP 4.3.4 (ISAPI).

On my website, there is a form to subscribe to the site as a member. To confirm the subscription, I send a mail to the person who has to click on a link to confirm the subscription.

I use so the mail() function to send the mail as text format but there is a random problem.

Sometimes (about 2-3 times per week) persons who receive the mail can't confirm their subscription and forward the mail to me and I can then constat the problem:

A little part of the body (the string "script") had been replaced by another string ("VOID").

This problem is not dependant with the Mail client (Outlook, Netscape etc.).

PHP 4.3.4 doesn't resolves this problem.

I am not arrived to reproduce this problem and it it seems to be totally random. It is a very strange bug!! An idea?

Reproduce code:
---------------
The code source is:

$message = "
Bonjour,

Pour valider d?finitivement votre inscription comme membre, merci de clicker sur le lien ci-dessous:
http://www.domain.com/inscription.php?code=$code
";

mail($email,"Inscription",$message,"From: mail@domain.com\r\nContent-Type: text/plain; charset=iso-8859-1");

Expected result:
----------------
Normally the person would see:

Bonjour,

Pour valider d?finitivement votre inscription comme membre, merci de clicker sur le lien ci-dessous:
http://www.domain.com/inscription.php?code=1587

Actual result:
--------------
But some persons obtain:

Bonjour,

Pour valider d?finitivement votre inscription comme membre, merci de clicker sur le lien ci-dessous:
http://www.domain.com/inVOIDion.php?code=1587