Gotic

The link to additional product description has a fatal error on all products listed on our website www.wholesalesportsne.com The error is exactly "Fatal error: Call to undefined method ProductController::getProduct()in/home3/wholetc7/public_html/shop/modules/productcomments/productcomments.php on line 734. We run version 1.5.0.17. I cannot figure out what the problem is. Please help me. also, on the main page the Home tag is massed up. The categories are listed twice. Any idea why?