howto create email list from register.php

[ptbyjason]

I am trying to update a email list database from register.php -- so far i have
in register.php i added the line -- $email appears to be the right string as well

$userid = $DB_site->insert_id();

////// CUSTOM CODE insert new email to email list database ///////

exec("curl 'http://www.domain.com/addtomaillist.php?theemail=$email'");

////// CUSTOM CODE //////

// Insert user text fields

----------------------------------

in addtomaillist.php i have

<?
include("../configure.inc");

if($theemail) {
mysql_query("INSERT INTO emaillist (email) VALUES ('$theemail')");

}

echo "done";

?>

the addtomaillist.php works i know for sure.. but im not getting the variable to pass it from register.php. I may have the custom line in the wrong area in register.php im not sure any help or suggestions would be appreciate.. im open to different ways of doing this ..