Stephen Fry took just minutes to reiterate his offer to pay the fine of Paul Chambers, the 27-year-old man convicted of "menace" after making a Twitter joke about blowing up an airport.

Chambers today lost his appeal against the conviction and £1,000 fine, Judge Jacqueline Davies dismissing his case on every count. The former accountant's offending tweet – "Crap! Robin Hood airport is closed. You've got a week and a bit to get your shit together otherwise I'm blowing the airport sky high!" – sent publicly to a Northern Ireland mother he met online, was found to be a menacing threat to security.

As news filtered out from the Doncaster courtroom, invariably through Twitter, the micro-blogging service was struck dumb, some of its most high-profile proponents tweeting their outrage.

The hashtag #twitterjoketrial is currently among Twitter's trending topics worldwide. Chambers himself has yet to post a reaction, apparently due to an unpaid phone bill.

Stephen Fry quickly tweeted Chambers reiterating the offer to pay his fine, which stands at £3,600 when combined with prosecution costs. "My offer still stands. Whatever they fine you, I'll pay", he said.

Chambers's friends and associates were reported to be "gutted" by the verdict. His partner, to whom the offending tweet was directed, posted: "My battery is dying. We are gutted. It's not the fine, this is stopping Paul getting a job and has ruined his life." His solicitor wrote: "English law relating to freedom of expression is not in a good state."

The comedian Dara O'Briain was rendered gag-less at the news. "An astonishing, ludicrous result in #twitterjoketrial. A victory for crushing literalism and scaremongering by the judiciary. Horrible," he wrote, later adding: "So that's the banning of sarcasm, irony, sub-text and any of the other subtleties of language that we use AS GROWN UPS." Fellow funnyman David Mitchell called the verdict "a disgrace", saying "he's being punished for flippancy" and "flippancy is important".

The Doctor Who actor and director Barnaby Edwards commented: "30,000 complaints to the PPC: Jan Moir 'not guilty'. One joke tweet: Paul Chambers 'obviously menacing'."

Simon Holcombe, aka @OllyAitch, encapsulated the reaction of many, commenting: "Joke (n.): Something said or done to cause amusement (may not apply on Twitter or within British judicial system)."