/* Error:
Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/.ren/fksource/facka.net/te/accounts.php on line 86
 */

// Check to see if the username is allready taken?
$checkuser = mysql_query("SELECT username FROM users WHERE username='$username'");
$username_exist = mysql_num_rows($checkuser);
if ($username_exist != 0){
// username taken...
}