Which PHP shopping supports specials and product discounts?

[mesh2005]

I think OScommerce supports discount on a single product, is there any PHP shopping cart that supports something like "buy three and pay for two"?
Thank you

[MrCoder]

OSCommerce would support it, look for a contribution or write your own.

[jeking]

Zen, based on OSCommerce, also supports discounts and specials. I found Zen to be better supported and MUCH more easily upgraded and modified than OSC.