The war of words followed a ruling by a county court judge that BT was in " clear breach of contract" for its failure to reactivate broadband connections at Capital Fortune's London headquarters following a 10-day outage.
Capital Fortune said in its complaint to Ofcom that BT had misled the media in its press statement after the ruling.
The BT statement read: "BT tries to provide the best service possible to all of its customers all of the time.
"We were already dealing with the fault that had caused a break in broadband service to Capital Fortune and we were already doing all we could to restore service to them as quickly as possible.
"There was no judgment on whether BT was in breach of contract because the judge did not consider that."
Rob Killeen, founder of Capital Fortune, explained that the mortgage company had "reported BT's inaccurate comments to the independent regulator" and that " BT's press response will only serve to undermine public confidence in [BT] as a company and, more importantly, the whole of the industry".
"Since going to court, BT has been heavy handed and improper. As well as claiming our action was an abuse of process, threatening costs and their own legal action, [BT] then circulated misleading information stating they were doing all they could and that the judge did not find them in breach of contract, " said Killeen.
"The judge found against BT on both issues yet [BT] informed the media differently. This is a flagrant disrespect of the court process and a slap in the face to all customers suffering similar difficulties.
"We have ordered the full recorded transcript of the hearing and will publish it on our website at Capitalfortune.com. BT can then publicly justify its comments."
Mike Bartlett, a spokesman for BT, told vnunet.com: "BT notes Capital Fortune's complaint to Ofcom and will comply fully with any investigation."
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