THEY are meeting again in the old house owned by the Finnish government, the Konigstedt Manor building in Vantaa, some 25 kilometers from the city of Helsinki. It is their fourth get-together and like the others is aimed at one objective: peace in Aceh. The negotiations between the Free Aceh Movement (GAM) and the Indonesian government were reopened last Thursday by Martii Ahtisaari, a former president of Finland who heads a conflict medi