This is a potty situation, surely?

The sponge space-cake was delicious, as were the filo parcels with ricotta, basil and bud

IF IT'S any consolation to the Welsh grandfather sentenced to a year's imprisonment yesterday for smoking cannabis to relieve his arthritis, at least this way he'll be guaranteed a regular supply without having to grow his own. Everyone knows that getting hold of pot in prison is a great deal easier than, say, finding an assistant in Sainsbury's to direct you to the organic carrots. "Organic" is the key word here. The 12 healthy marijuana plants that Inspector Knacker and his boys found when they busted Mr Eric Mann in his Pembrokeshire attic were prize specimens of bio-dynamic horticulture - no pesticides, no organic phosphates, no toxins.

Let's hope his suppliers over the next 12 months will be as meticulous about the quality of their merchandise, though let's face it, most people would be pushed to tell whether their after dinner spliff had been sprayed with DDT or fertilised with the well-rotted ordure of last year's Derby winner. I know I couldn't.

When I talked about the Welsh Connection to my friend Lester Grindspoon yesterday, his chief concern was that even now Mr Mann was being prescribed some really dangerous drug to relieve his arthritic symptoms by well-meaning prison authorities - aspirin for instance.

Sorry, have I mentioned my friend Lester before? His full title is Dr Lester Grindspoon, Professor of Psychiatry at Harvard University Medical School. We first became acquainted when I published an account of the extraordinary effects that smoking cannabis has on my appalling eyesight - I have a tiresome condition known as RP, retinitis pigmentosa. Professor Grindspoon immediately sent me a copy of his latest book on cannabis, Marijuana - The Forbidden Medicine, a sequel to his best-seller Marijuana Reconsidered, first published in 1977 and recently reissued by Harvard University Press in their all time classic series.

To describe Professor Grindspoon as being in favour of cannabis is a bit like calling Michael Schumacher a Sunday motorist. Professor Grindspoon reckons that in years to come people will regard the first decade of the next millennium in medical terms as the cannabis decade, in much the same way as they associate penicillin with the Forties. "They'll call it the wonder drug, and that's precisely what it is," he told me on the phone from Massachusetts. "No side-effects; no one's ever died from using cannabis. Do you know that in the US up to 2,000 people die from aspirin poisoning every year? Cannabis not only works for RP, glaucoma, MS, arthritis and weight recovery for Aids victims, but it's absolutely safe."

I said gloomily that I wished he'd been on the radio phone-in I did the other day. In the blue corner me pro-cannabis; in the red corner a fierce Glaswegian drugs counsellor who said she could give us 20 case histories of hardened heroin addicts who had started out smoking pot. "Ah, the gateway hypothesis," said Professor Grindspoon. "It's never been proved. On the contrary, they did a survey the other day where they questioned 100 heroin addicts about the drugs they'd started out taking. Ninety-eight per cent said coffee, 95 per cent said alcohol, 92 per cent said Coca-Cola. Very few of them had ever smoked pot."

Two years ago Lester and the then US attorney General Ramsey Clarke made an 11th-hour mercy dash to Kuala Lumpur where an American tourist, Kelly Wiley, had been found guilty of possessing cannabis and was due to be executed in a couple of days. The chief prosecutor told Lester cheerfully that he'd already had 100 Malaysians executed for possession, but hanging his first American would almost certainly result in a top government job. Lester had brought with him X-rays of Wiley's arm, which had been injured in an accident 20 years earlier. The bones had never properly healed, and to relieve the pain Wiley regularly used cannabis. The judge studied the X-rays, Wiley got off, the prosecutor never got his top government job. "Tell your readers, if they're interested they can log on to our website for all the latest medical information we've collated on the subject," says Lester. "I'm now working on another book, The Uses of Marijuana, which spreads the net much wider, illustrating how useful creative artists have found it in their work."

It suddenly occurs to me that among the sackloads of mail I got following my dope-smoking piece there was a slim green paperback called Cooking with Ganja by someone calling himself simply "Eric". Good heavens, could that possibly be the arthritic grandfather from Pembroke Dock currently detained at Her Majesty's pleasure? If it is, thanks Eric. The all-in- one sponge space-cake was delicious; as for the filo parcels with ricotta, basil and bud - mmm, wonderful. If I were charitable I'd do a Sydney Carton and stand in for you - heaven knows I broadcast my crime often enough and, what's more, that my kids supply me - but hang on, was that a knock on the door?