Will the card format in the Tampax? Always best to format in the device for which it is being used, but I would be surprised if the camera won't do it. If so, then go and ask the supplier for another one. You shouldn't really have this problem with a mass consumer product, (which it soon will be) so it could be a duffer.
Conan
PS If it does fail in the camera(s) then it might just be worth a quick check to see if the manufacturers have released a firmware update. If they have, then just don't load it with the 4GB card :-)