Ability to cart products whose date is greator than now

Hi, i want to use open cart 1.4.9.1 for a reservation front end. I need to show the client the date when the product is available. The client also needs to be able to specify his due date (as an option on the product), in which case if the date the product is available is greater than the clients due date, then an error is flagged (something like product only available beyond this date).

I have kind of modified the relevant files to show products whose available dates are in the future; but the problem is that i can't cart such a product, and also can't find the files where to set up the logic that can flag the above error. I know this shouldn't be hard and someone on the forum can be of great help.

Thanks

Hey folks on the forum, someone needs to assist here, this ain't a spam bot flagging the request!! I need he......lll.....p!!
Danke

Hi, could it be that there is some kind of ajax validation on the add to cart button, such that when you add a product whose date available field is greater than now, its rejected by the cart???