It is a Thursday night before a holiday weekend, and the Frank Ryan & Son pub on the north side of the River Liffey is starting to fill -- as it has for decades -- with a mixture of working men and office types from the law and banking concerns on the other side of the quay.

As the dark Guinness is poured and the faces grow more flushed, a steady stream of customers flows past the century-old mahogany bar and the age-darkened stools and out the back door.

It's not a whiff of fresh air they seek, but tobacco smoke.

Yes, the smoky pubs of Ireland, the haunts of such literary luminaries as James Joyce and Brendan Behan, immortalized by poets and peers, have joined the 21st century as clean-air zones. And although the famed revolutionary spirit lives on in word, it does not necessarily in deed.

Ever so meekly have Irish smokers submitted to a new law that fines them up to 3,000 euros [more than $3,600] for puffing in the taverns.

Ireland boasts the toughest public anti-smoking law in Europe, and anti-tobacco activists are watching the Emerald Isle's experiment to see whether it can be expanded across the European Union, following the example of many states and cities in the United States. On June 1, Norway joined Ireland in outlawing smoking in bars and restaurants, with Sweden slated to be the next to follow suit.

For those who frequent Irish taverns, there is more than a trace of nostalgia, even as they submit to the strictures meant to protect their health and the health of the hospitality industry workforce.

The law bans smoking indoors in almost all places, the chief exceptions being private homes, prisons and mental hospitals.

"The only pleasure left anymore is in prison, or in a mental hospital," said patron George Allis. "At times, I feel like going in there and knocking on the gate and asking them to let me in."

Removing smoke from the air in pubs is no cause for an Irish wake, defenders of the ban insist.

"It's not the smoke-filled rooms people come for, it's to come for the craic," Ivor Callely, Ireland's junior health minister, said on the BBC's "Today" program, using the Gaelic word pronounced "crack" that can be liberally translated as: good music, good people, good conversation and good times.

Two months into the ban, pub owners -- many of whom initially opposed it -- are learning to live with it, said Seamus O'Donoghue, the new president of the Vintners Federation of Ireland, a trade group.

"There is a little bit of members complaining they have lost a lot of business, especially in rural areas," he said. However, "urban areas are taking it on board and dealing with it."

The urban-rural divide, he explained, is because in the country people tend to be more set in their ways and often do not have a choice of local pubs. If a country pub is the closest one for miles, and it has no outdoor smoking area, the pub-goers who smoke are sunk. "If the facilities are not good, or there is inclement weather, they'll drink at home," O'Donoghue said.

Minister of Health Micheal Martin initiated the legislation for the prohibition based on a January 2003 study on the effects of environmental tobacco smoke. The study said that second-hand smoke raises the chances of contracting lung cancer by as much as 20 percent to 30 percent, heart disease 25 percent to 30 percent and stroke by as much as 82 percent.

"We are very pleased by the level of compliance to date with the new legislation," Pat Montague, a spokesman for Ireland's office of tobacco control, said in an e-mail.

"The public support for this measure has been very strong throughout -- an opinion poll in November showed that 66 percent supported its introduction in pubs and bars, with 81 percent believing that the law should be obeyed by publicans, including 61 percent of smokers," he said.

Ireland's Office of Tobacco Control published a study recently saying 97 percent of bars and restaurants inspected during the first month had been smoke-free and that the ban had not resulted in a decline in business. In fact, attendance at bars and pubs was at about the same as before..

In Ryan's, as one pint of cool, smooth Guinness foamed next to a glowing open fire that illuminated walls and shelves full of bric-a-brac -- a stuffed otter, old crockery, winner's cups, and a framed newspaper clipping with the headline "Big Frank's 50 Reasons To Be Happy; Top Publican's Birthday Bash" -- patron Michael Fitzsimons, a 32-year-old attorney from Drogheda, said the ban was having its intended effect. "To be honest, you smoke much less, but the ban coming in makes you want to smoke more," he said. "'The moment I come in, my gut is saying, 'I'd love a cig outside.' "

Ken Ryan, Big Frank's 32-year-old son, said the pub is much cleaner and easier to tidy up at the end of the day. (The pavements outside many taverns, however, are another matter.)

Nevertheless, few topics have in recent years stirred Dubliners as much as the tobacco ban, said Ken Ryan, noting that his customers were "still talking about it nonstop" more than a month after it took effect.

At Ryan's, smoke or no smoke, the 'craic' kept the bar bubbling gregariously, while a small sign near the cash register carried a message suited to the expansive mood of the evening.

"When I gave up smoking, drinking and sex," the sign read, "it was the most miserable hour of my life."