Two young dancers in traditional costume perform before Prime Minister Costas Simitis and his wife Daphne during a caroling call on the prime ministerial residence on Monday. President Costis Stephanopoulos and opposition leaders received similar visits. And around the country, children in more conventional dress went from door to door singing the traditional Christmas Eve carols in what is one of the year’s major pocket money boosters. Severe storms last week caused chaos throughout the country, severing road and rail links between northern and southern Greece on Friday. At the same time, fog forced Thessaloniki civil aviation authorities to keep the local airport closed for hours, as the only runway that was equipped with electronic equipment to guide pilots in through minimal visibility had been left covered in snow and ice.