T-Mobile isn't alone in its innovative reading of Ofcom recommendations, but at least the company only implied that the regulator was responsible for the increase in its prices: O2 is claiming it outright.
0870 numbers are non-geographic: they are national calls regardless of where the call originates or terminates. Mobile operators have until now treated such numbers as exceptional and charged a special rate for them, but UK-regulator Ofcom has stated that such calls are to be treated as normal national calls and that they "should" be included within bundled minutes that come with the tariff.
The key word here is "should", which T-Mobile interpreted as "don't have to be", enabling the company to double its prices. The other UK operators are taking much the same approach, while intimating that the change has been forced on them by Ofcom, but O2 went one stage further in an e-mail to a customer last week which clearly laid the blame at Ofcom's door:
Our old tariffs had calls to these  numbers included in the free allowance but as per the special number policy of Ofcom, we've excluded these calls from the free allowances of our tariffs with effect from 28 September 2008.
This is, of course, bollocks. When we put this to O2 we were told that it had "...advised customer services that this is a business decision", but apparently customer services isn't taking this advice as punters are still being told the same thing this morning.
We asked O2 about that, and Ofcom about how it feels to be completely ignored by the industry you're supposed to be regulating, but so far neither party has got back to us. ®