W7100A custom MAC problem

Dear Support,

We ordered 80 piecies of W7100A (unfortunately not s2e) modules and we get into some troubles. After uploading S2E firmware, we encounter problems in assigning custom MAC adrresses. It seems like the MAC adrress must start from WIZnets 00:08:DC, because in other way after resetting the device, our MAC address is replaced by 00:08:DC:00:00:01.
I would like to know if is it possible to use WIZ S2E firmware without WIZnets MAC address and if not, may we purchase 80 MAC adrresses which starts from 00:08:DC?

Best regards,
miki