<?php

// this will fix the "add to cart" bug.
// we need to refetch the products to get our custom attribs
$products= Mage::getModel('catalog/product')->getCollection()
    ->addAttributeToSelect('rbanh_type')
    ->addAttributeToSelect('rbanh_price')
    ->addAttributeToSelect('rbanh_color')
    ;
$product2 = $products->getItemById($product_id);

$rbanhtype = $product2->getRbanh_type();
$rbanhprice = $product2->getRbanh_price();
$rbanhcolor = $product2->getRbanh_color();