Online Store cart confirmation issue!

[tdoes]

How can I correct this issue?  I have an Online Store cart confirmation issue!  When the link to confirm purchase is clicked I get this message!
Fatal error: Call to undefined method VirtueMartModelCustomfields::getProductCustomFieldCart() in /home/content/24/7601124/html/madmenunltd/administrator/components/com_virtuemart/models/orders.php on line 803

When I go to this line in question I see    $productCustom = VirtueMartModelCustomfields::getProductCustomFieldCart ($selected );

Is this enough information to see what the flaw is?

Running Joomla 2.5.8 / Virtuemart 2.0.18