When you're smiling, the whole world will not necessarily beam along with you. Indeed, your happy visage could stop you seeing as much of the planet as you would wish. From next month, applications for passports by Canadians will be rejected if the photograph of the would-be traveller shows a smile. "What we're asking is that there be a neutral expression," says Marina Moraitis, manager of communications at the Passport Office in Ottawa.

Canada introduced the rule, she says, to comply with a recommendation issued globally by the International Civil Aviation Organization (ICAO). "With the introduction of biometrics, the contour of the face is changed by a smile," she says. "Canadians wishing to travel to countries using facial recognition may be disadvantaged." Mrs Moraitis' task is made easier because all pictures for Canadian passports must be taken by a professional photographer. "Booth photos are not accepted," she says. They have all been briefed to try to ensure that no one breaks into a smile in the studio.

The new measure has already officially taken effect, but there is a two-month grin amnesty in progress. Cheerful Canadians have until 3 November to wipe the smiles from their faces.

The UK Passport Service makes no such stipulations. Perhaps it thinks the 27 per cent increase in fees this week will dismay the gladdest traveller. But elsewhere even a Mona-Lisa like smirk could get into trouble.

The US insists on "mouth closed, eyes open and looking directly ahead". It even specifies the clothes you must wear: "normal street attire". Australia demands that the photograph must have "no toys, chair backs, parents or siblings visible". Officials in Washington and Canberra would no doubt be unimpressed with the Photo-Me booth installed at Warwick University. As previously mentioned, last time I looked the white panel at the back bore the words - in thick, indelible black ink and just above head height - "This person is an international terrorist".

Few of the world's borders make travellers smile - particularly in parts of the world where international frontier posts, or more specifically the people trying to cross them, constitute a key source of revenue for the local economy.

Pity the poor tourist who fondly believes that Jack Straw's admonishment on the inside front cover of a passport carries the slightest weight in Mogadishu or Managua. Her Britannic Majesty's Secretary of State can request and require that the bearer should be allowed "to pass freely without let or hindrance", but that cuts little ice at far-flung frontiers of the planet. Border officials hold all the cards. They are endowed with all the time in the world. And they know it.

Deadlock is all the more discomfiting when you are stuck in an airless, cheerless and tea-less room. After three hours at a fly-blown frontier post on Vietnam's side of the border with Cambodia, the official explained there was only one way to resolve an apparent irregularity with the visa that I had acquired after a series of visits to the Vietnamese Embassy in London a fortnight earlier: a fee of $50 cash would do the trick.

A small wad of hard currency bought a meticulously impressed stamp in my passport, a flourishing signature and a handshake.

The bus that had brought me to the frontier from Phnom Penh had long since departed for Ho Chi Minh City. In one sense I wasn't sorry to see it go. It still bore the livery of RATP, the Parisian transport authority. Cramming commuters into these no-frills buses for short hops around the French capital is one thing; they are less than ideal for 12-hour trips with a similar number of passengers over roads still unrepaired since the American bombers last went in. But the disappearance, into a cloud of dust, of a bus still claiming to be number 56 to Porte de Clignancourt left me with a problem: how to cover the 75km to the city formerly known as Saigon?

No problem, explained the official now enjoying custody of my dollars. His "cousin" was outside, and happened to be the proud owner of a taxi. Once a few more passengers had turned up for their ritual shakedown, he would be delighted to depart for Ho Chi Minh City for a very reasonable $25 each. Payment in advance. I had so far seen no more than 50 metres of Vietnamese territory, and spent the equivalent of £50 - a rate of £1 per metre. But sometimes the traveller has to smile and pay up.

A decade later, on Tuesday this week, I found myself in strangely similar circumstances: grinning inanely and handing over £68 in the hope of being allowed through a heavily guarded gate, in order to travel a total of about 50m. The funny thing was: the location was Bournemouth, and I wanted to travel the short distance from the West Cliff Road to the tennis court of the Highcliff Marriott Hotel. A curious destination, you might think, but there was a purpose behind it. I was due to chair a meeting on transport, one of the dozens of fringe events that accompanied the Labour Party conference this week. The tennis court's net had been removed and a marquee erected, where around 50 delegates were nibbling canapés and discussing the Prime Minister's speech. The location, though, was inside the security cordon, into which access was possible only for those with official accreditation.

The sideshows at political conferences are planned well in advance, which allows everyone time to organise the necessary identity card. I had posted off the forms to the conference office well in advance, and been instructed to pick up the pass on the day from a window of the Pavilion Theatre. When I smiled at the staff handing out the precious passes, the feeling of unbelonging was remarkably similar to the day I turned up at Luton airport to catch an easyJet flight to Geneva that was due to depart from Gatwick. I was not on the Labour Party's list, so I would have to go next door and apply again from scratch.

What was that party anthem again? We'll keep the red tape flying here? To be instantly beamed back to the Soviet consulate in London in the 1980s, visit the Late Accreditation Office at the Labour Party conference.

The workers assigned to the task were trying their best to deal with a horde of hopeful conference-goers. But they were plainly understaffed and overstretched. One whisper maintained the waiting-time for a pass was three hours, another insisted it was five. Towards the end of the afternoon I met one photographer who had joined the queue twice, the second occasion to ask for a refund: her pass would not be ready in time for the event she had planned to snap.

In keeping with the no-frills regime popular among Iron Curtain consulates, facilities were minimal. Cigarettes were on sale, but not tea. The only public telephone was outside, which presented a problem for journalists whose mobile phone batteries had expired; the only mains socket was powering the cigarette machine. Even though the Prime Minister's speech was taking place inside the conference hall, an event that some of the waiting masses might possibly wish to hear, there was no TV or audio feed. Before the battery on someone's portable wireless ran out, we faintly heard Mr Blair say, "With cheaper air travel, and all the problems of fraud, it makes sense to ask whether now in the early 21st century identity cards are no longer an affront to civil liberties, but may be the way of protecting them?". Not if you run the system like this, pal, was one queuer's response.

The minutes were ticking rapidly towards the start of two concurrent fringe events: the Police Federation's session on "Bureaucracy and Red Tape" and the event that I was due to chair. Finally a staff member approached with a pass on which I was cheerfully displaying decades of NHS dental care. I thanked her, grabbed the card and ran to the nearest security checkpoint. I handed over the card, together with my passport as a second form of ID. "You can't come in," the police officer said.

This was not the same man who had obstructed my admission to Vietnam, and he was clearly not after some hard currency. What was the obstacle? Had I not expended money, nerves and a dismal afternoon in the Labour Party's twilight zone to procure my prized badge?

"They don't match."

Closer inspection revealed that his refusal was entirely justified. The passport showed my real name, and the identity card displayed my photograph. Unfortunately, given the imminence of the fringe meeting, the pass was made out in the name of the industrial editor of a Sunday newspaper. Now that's what I call an identity crisis.

The other purpose of my visit to Bournemouth was to corner Stephen Bath, outgoing president of the Association of British Travel Agents and joint boss of Bath Travel. I wanted to find out why he is discriminating against travellers under the age of 10 (see Warning of the Week, below). Mr Bath's company is based in the resort, close to the conference HQ. "Call in any time after lunch," he had invited. The afternoon had burned up in a bureaucratic haze. To rescue something from the debacle, I borrowed a phone to track down Mr Bath . It transpired that he was soon to be interviewed by Matthew Bannister, who was broadcasting on Radio Five Live from the conference venue. Splendid, I thought, I shall wait for him outside. But Mr Bath was nowhere to be found. Rather than endure the security checks, he had opted to drive 30 miles from his office to a BBC studio in Southampton, in order to talk to a presenter back in Bournemouth.

"WE ROLLED up to the Afghanistan border at Islam Q'ala and could find no sign of officialdom." Different times, as Tony and Maureen Wheeler describe in the 30-year-old Across Asia On The Cheap, the book that launched a travel publishing legend and many millions of trips. "Eventually we found a group of rather stoned-looking Americans sitting on the floor in one building." "'Where's everyone?', we asked, and got the obvious answer: gone for lunch.

"'How long have you been here?', we asked. 'About six hours.'

"'Good grief, what have you been doing all that time?' 'Blowing a little dope with the customs.'"

That might bring a smile to the face of the most jaded traveller.