Preposterous! I'm trying to give Ikea my business!

What a farce. We were trying to buy an item from Ikea, the Swedish furniture empire. Turns out they have an online shop. Good-oh. Turns out they deliver to my area. Good-oh x2. So I started filling in the login/delivery forms on the shopping basket/checkout system. I entered all my card details and hit 'Submit'. 10 seconds later I see the above error. Hmm.... Not good. I phone the number and the guy says 'Are you trying to use our online shop using a laptop?' What? Why on earth should that make a difference? 'Ah, he says, our system doesn't work with laptops'. But, I spluttered, that should make no difference whatsoever. Don't you mean that it doesn't work well with err.... Vista? I said, striking out in the dark? 'Ah yes, it also doesn't work with Vista or Firefox. Or laptops' he said. I asked if I could give the phone guy my order instead. 'Oh no, we don't take phone orders'. Quite staggering. I'm trying to give this com...