table event email issues...

i have a table event setup to send out notifications when data changes or is added and for some reason we aren't getting the email notifications, i have checked my providers spam box and they aren't in there, just wondering if you could tell me where i might begin troubleshooting this. here is the event code in case you see something i might have wrong in it:
function AfterAdd()

{

// ** Send simple email ****
$email="corporate@pleth.com";

$message="a new project has been added to the pleth networks project board, please visit: http://www.pleth.net/php-intranet/ to login and view this project's details.";

$subject="Pleth Project Manager";

mail($email, $subject, $message);

}
thanks for your help in advance,
Cotton Rohrscheib, Partner

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