Hello I have added the shipping contrib for canada post to include dimensions and weight . This is version 3.7 found on oscommerce contribs. However when i go to checkout a product I get this error.

Fatal error: Call to undefined function: get_shiptotal() in /.../..../public_html/catalog/includes/classes/shipping.php on line 23


lines 23 to 25 of shipping.php reads:


// BOF: Individual Shipping Prices
$shiptotal = $cart->get_shiptotal();

// EOF: Individual Shipping Prices

Can anyone help me here? Thanks