Hey I was having the same problem. For me it was only doing this when not using taxes. The solution that I found was to open the paypal-standard.merchant.php located in the wspc-merchants folder of the plugin go to line 263 where it reads:
if (!$aggregate) {
foreach ($this->cart_items as $cart_row) {
$paypal_vars += array(
"item_name_$i" => $cart_row['name'],
"amount_$i" => $this->convert($cart_row['price']),
"tax_$i" => ($add_tax) ? $this->convert($cart_row['tax']) : 0,
"quantity_$i" => $cart_row['quantity'],
"item_number_$i" => $cart_row['product_id'],
// additional shipping for the the (first item / total of the items)
"shipping_$i" => $this->convert($cart_row['shipping']/ $cart_row['quantity'] ),
// additional shipping beyond the first item
"shipping2_$i" => $this->convert($cart_row['shipping']/ $cart_row['quantity'] ),
"handling_$i" => '',
);
++$i;
}
I changed change tax_$i to just tax and it seems to be working.
Hopefully this helps.
Adam Webster
