Malaysia and Indonesia begin ministerial talks in Kuala Lumpur today about one of the most dangerously porous borders in southeast Asia - between Indonesian Kalimantan and the Malaysian states of Sarawak and Sabah in Borneo. A flourishing trade in illegal workers, illicit timber, guns and drugs continues across the borders. As the richer country, Malaysia receives thousands of illegal migrants seeking work and allegedly connives with corrupt Indonesians to smuggle protected logs on to the world market through borders. There are several documented cases of eager militant Muslims from Malaysia entering Indonesia freely in northeast Kalimantan, from where they travel across Sulawesi to join religious fighters in Maluku or to take part in attempted bombings in Jakarta. 'The upcoming joint commission meeting will focus on efforts to amend an existing memorandum of understanding on Indonesian migrant workers and the increasing incidence of illegal logging, illicit arms trafficking and human trafficking along the border of the two countries,' Indonesian Ambassador to Malaysia Hadi Wayarabi said after meeting President Megawati Sukarnoputri on Friday. Mr Hadi said syndicates trafficking children and illicit arms were operating freely along the border in Kalimantan. 'The President has asked the police to pay attention to many criminal activities along the border,' he said. The new concern stems from several recent incidents. Indonesia's labour experts are worried by Kuala Lumpur's recent decision to halve the number of Indonesian workers in Malaysia following a riot last month. About 500,000 Indonesians are estimated to be working illegally in Malaysia. Mass deportations have begun and fears are rising about how the return of the workers will affect the already swelling numbers of unemployed in Indonesia. Investigations by the British-based Environmental Investigation Agency and its Indonesian partner Telapak have proved collusion between illegal logging tycoons in West Kalimantan and their counterparts in Malaysian government-linked firms in Sarawak. Protected log species such as ramin are looted from Indonesian national parks and given official seals in Malaysia to allow their release on to world markets. The trade in women, small arms and drugs are less well documented but just as worrying. Of greatest international significance is the porous nature of the border at a time when the US and its allies are trying to prevent the spread of militant Islamic movements, which are able to move men and materials freely throughout southeast Asia. The corruption of local police, army and bureaucratic personnel on both sides will be formidable obstacles to any effort to clean up the border.