[PHP 5.0 mail() function acting VERY weird]

I didn't know that mail() returned boolean, but I'll turn on errors and see what I get.

[PHP 5.0 mail() function acting VERY weird]

I run PHP5 on a Linux (Ubuntu) box.  The setup has been working for years without a problem, sending E-mails to my local address via web pages and PHP.

 

Today, I'm trying to write a simply page to send me an E-mail.  No E-mail, no error, no nothing.  However, it WILL send the E-mail if the text is something else.  After HUNDREDS of E-mails to myself to test this, I have come up with the following:

 

This works:

<?php
$mailtext = "e'a'to";
mail('myaddress@mydomain.com',' My subject', $mailtext);
?>

 

BUT....If I take out any character from $mailtext, or substitute any other letter, the mail will not be sent.

 

Just to be silly, I tested this, and it works:

<?php
$mailtext = "This is a sample E-mail";
mail('myaddress@mydomain.com', 'My Subject', $mailtext);

 

But this doesn't work:

<?php
$mailtext = "This is a sample Email";
mail('myaddress@mydomain.com', 'My Subject', $mailtext);
?>

 

Very weird combinations of characters in $mailtext will get sent just fine, but change it at all, and the mail won't get sent.

 

Any ideas?