Problem with writing of url

[HUSSON2013]

Hello
I use in the form of the product the address url of the product (url extern - that of the manufacturer)

It appears in a button to the place of that to Add to cart and it works correctly.

But there is a problem with the writing of the url which is not correctly made.
They appear as this:
index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id=145&virtuemart_category_id=http://www.laredoute.fr/achat-femme.aspx?categoryid=22890157

While it should be as this:
index.php?option=com_virtuemart&Itemid=655&view=productdetails&virtuemart_product_id=145&virtuemart_category_id=5

It  misses Itemid of the menu with whom is connected this product (in the example: Itemid=655) and the number of category_id is replaced by the external url (in the example: http://www.laredoute.fr/achat-femme.aspx?categoryid=22890157)

Thank you for your help

François

Virtuemart 2.024
Joomla 2.5.16