In Athens she will be competing as a Sudanese, an extraordinary leap of allegiance which breaks no rules but demonstrates the shortcomings of the system.

Nationality in sport, once clear-cut, has become seriously muddied following the break-up of the Soviet bloc and the increasing transfer of talent from poor to rich countries.

Weightlifters born in Albania and the Soviet Union will represent Greece at the Athens Olympics while some of Kenya's top middle-distance talent will wear the colours of Qatar. Australia's canoeing team features a former Mr Bulgaria.

Perhaps most bizarre of all is the case of Merlene Ottey who won a clutch of Olympic medals for Jamaica at six Games. In Athens she will race in the colours of Slovenia.

Aldama last represented Cuba at the 2000 Olympics and her native country sticks rigidly to the International Association of Athletics Federations' (IAAF) rules which say three years must pass before an athlete can compete under another flag.

Once the three years were up, Aldama had to find another country. She has lived in Britain since 2001 with her child and has a British husband, who is serving a 15-year jail sentence for supplying heroin.

However, Britain takes a hard line on residency and Aldama feared she would not be eligible in time for Athens.

Media reports said she put out feelers to Italy and the Czech Republic but eventually Aldama picked Sudan, a nation with little Olympic heritage and a swift citizenship process. Aldama appears to have no connection with the African country.

Clutching her Sudanese passport, she contacted the IAAF early this year and it gave her the green light to compete.

NOVEL ELEMENT

Ottey, now 44, was luckier. She last raced for Jamaica at the Sydney Games where she won a relay silver and she has been living in Slovenia since 1998.

She was granted Slovenian citizenship in May 2002 and Jamaica allowed her to compete for her new nation immediately.

The Aldama case adds a novel element to the nationality issue: she has chosen to move to a developing country so she can compete whereas most cases involve athletes moving to improve their personal or financial situation.

The collapse in the early 1990s of the Soviet bloc, which had placed great emphasis on sporting achievement, led to an exodus of top athletes and coaches desperate to further their careers in countries where ample funding was still available.

Greece naturalised Albanian Pyrros Dimas in 1992 and he went on to win three Olympic weightlifting golds. Canoeist Martin Marinov won bronzes for Bulgaria in 1988 and 1992, and after winning the Mr Bulgaria title in 1993 he moved to Australia.

Communist states such as Cuba and China, where sporting achievement is a symbol of national pride, have traditionally taken a hard line on departing athletes.

Gao Jun, a table tennis silver medallist at the 1992 Barcelona Games, subsequently married an American and left China for the United States.

At the time the sport had a five-year no-competition rule for those switching countries and China stuck to it. However, Gao Jun came back to play for the U.S. in the 2000 Games.

Cuba's former Olympic champion Alberto Juantorena has described the movement of talent from his Communist homeland to richer countries as sporting prostitution.

Before the 2000 Games, the Caribbean island prevented then long jump world champion Niurka Montalvo from representing Spain even though she had lived in Spain for nearly three years.

OLYMPIC CHARTER

As long as regulations were obeyed, international officials had few problems with the nationality changes.

They point to the Olympic Charter which reads: "The practice of sport is a human right. Every individual must have the possibility of practising sport in accordance with his or her needs."

But the recent entry of oil-rich countries such as Bahrain and Qatar into the equation has caused widespread disquiet.

Kenyan Stephen Cherono, running under the name of Saif Saaeed Shaheen, won the 3,000-metre steeplechase gold for Qatar at the 2003 world championships. More than 10 Kenyans represented different nations at the Paris event.

Their change of allegiance, triggered by the offer of large salaries, was possible only because of a clause in the IAAF's rules that allows the three-year interval to be reduced to one if both countries agree.

The defections were criticised by International Olympic Committee (IOC) president Jacques Rogge.

"What we don't like is athletes being lured by large incentives by other countries...giving them a passport when they arrive at the airport," Rogge said.

"From a moral point of view we should avoid this transfer market in athletes."

In Athens the complexity of the problem will be further demonstrated by the Greek baseball team at their "home" Games.

The squad contains only one Greek-born player. The vast majority are north American-based players most of whom have never visited the country and qualified only through having Greek grandparents or great-grandparents.