I could be mistaken (won't be the first time and probably not the last), but manufacturer's usually only certify things that are available at the time of production... This would be the primary reason why they may say that it isn't recommended or doesn't work... Until Vodaphone goes back and actually tries it themselves, they won't certify it... but others, as usual, have gone ahead and plunged into the unknown and tried it out and say that it works... So, go for it with our blessings and if you need assistance, someone will only be to happy to errrrr... assist... yeah, that's the right word...
