Updated Vodafone has urged iPhone 4S owners to not upgrade to iOS 6.1, the latest available, because it believes the software jams 3G and phone connections.
Vodafone claimed that the bug is Apple's fault and that it affects Voda's rivals as well as its own UK network, although it only named Three Austria* as another impacted telco. The warning comes amid reports that iOS 6.1 overwhelms Microsoft Exchange servers and is apparently crippling some corporate networks.
In emails and texts to customers, and a forum post here, Vodafone told iPhone 4S fanbois to skip version 6.1 of Apple's mobile operating system until the Cupertino giant fixes the connectivity performance bug.
In a statement that branded the flaw an "iOS software fault", Voda squarely laid the blame on Apple. The telco described the nature of the problem for affected users thus:
We're aware of an issue caused by Apple iPhone 4S handsets that have been upgraded to iOS 6.1 which impacts performance on 3G. Some customers may occasionally experience difficulty in connecting to the network to make or receive calls or texts or to connect to the internet. These connection problems are intermittent.
The problem is exacerbated if "a significant number" of iPhone 4Ss running 6.1 are in the same area of the mobile network, an email from Vodafone sent to corporate customers and seen by The Register confirmed - and all phone users are affected by the fruity overload:
If there is a significant number of iPhone 4S handsets connecting to the network in a specific area, this can cause congestion issues for those users as well as the users of other handsets in that area.
Vodafone UK told The Reg that the problem was not specific to its network. However, O2 has reported no problems. EE (which operates the T-mobile and Orange brands in Blighty) told El Reg it is investigating but could not say whether or not there is a problem with its network. Three UK said it had no problems and could not comment on Three Austria.
When pressed on the technical cause of the overload, Voda's spokeswoman simply said "you'll have to ask Apple about that". Apple has not replied to a request for comment - indeed, it won't even talk to the BBC on this issue. ®
Updated to add
* A spokesman for Three Austria has been in touch to say: "We are facing the same problem, but not all customers using this upgrade are facing problems. To be on the safe side, we have sent a SMS to all 4S customers proactively to warn them NOT to download the actual upgrade."
The Austrian network added it is trying out test firmware from Apple as it investigates the issue.