Ticket #1487: 1487.patch

wp-register.php

@@ -30 +30 @@
   if ( username_exists( $user_login ) )
                 $errors['user_login'] = __('<strong>ERROR</strong>: This username is already registered, please choose another one.');
 
+        /* checking the email isn't already used by another user */
+        $result = $wpdb->get_results("SELECT user_email FROM $wpdb->users WHERE user_email = '$user_email'");
+        if (count($result) >= 1) {
+                die (__('<strong>ERROR</strong>: This email address is already registered, please supply another.'));
+        }
+
         if ( 0 == count($errors) ) {
                 $password = substr( md5( uniqid( microtime() ) ), 0, 7);