Wrong "ask for price" display when product has one son with zero or null price

[SteP[IT]]

I have many products with sons, where each son is a multiple quantity of the father product (ie, software license for 1,2,3,4,... users).
I need to set an empty price for the last son in the list, to get it showing the button "ASK OR PRICE": in this way the user can send a price request in the case the other product sons did not fit his needing (for the example of sw license, I can set sons for 1,2,3....99 users, and set one more son as 'more than 99 users' at no price to let the user ask for price).
But in VM 2.0.22b it doesn't work at all.
If you leave the price field empty, when selecting that son the product price shows the father price.
If you set the price to zero, the 'ask for price' bitton shows correctly, but you can still add the product to the Cart (obviously with zero price)
Could you please check it, and find a patch?
Thank you in advance

[chiller99]

That is the same as i posted in this topic:


http://forum.virtuemart.net/index.php?topic=116365.0

Hopefully somebody can help us with this.