Same happened to me after I got the 0€-bug. They didn't have time to cancel the order, and I received it on Wednesday; but today I got a phone call from Nokia France, they told there were two problems with my shipment: 1) invoice problem, 2) technical problem on the shipped series.

They told I should send back the device, and that I'll have a new coupon to purchase another one. I thought the technical problem was just an excuse to let them fix the invoice problem (AKA make me pay 99€), so I used my new coupon to get another n810 (this time at the planned 99€), then called back to ask if, now that I've paid, couldn't they just admit there was no technical problem, not deliver the 2nd n810 and let me keep the one I already have, in order to spare work to them and me.

But she said that there really was a technical problem. I doubt it, but just in case, and because I'm honest ;-), I'll ship back the n810 I got -- but only after I got the new one!