THE article by Jonathan Chamberlain on the Tung Tau dispute (Sunday Morning Post, August 29) did a considerable service to the children of Hong Kong. It also did a considerable service in highlighting the strategic nature of the issues involved. Special-needs children have special rights under the United Nations Convention on the Rights of the Child. Hong Kong and the Hong Kong Government are parties through the United Kingdom Government to that convention, and have inescapable obligations concerning these children. Briefly, the convention acknowledges ''the right of handicapped children to special care, education and training designed to help them to achieve the greatest possible self-reliance and to lead a full and active life in society''. The convention also embodies the fact that all rights apply to all children without exception, and that there is an obligation to protect children from any form of discrimination, irrespective of obvious issues like race, colour, sex, religion and also (quite specifically) disability. There is an obligation not to violate these rights and, more importantly, the Government must take positive action to promote them. Mr Chamberlain is trenchant in focusing attention on the wider issues. The development of the rights of children in Hong Kong to the level where their status is equated to, rather than subordinate to, adults is a vital area of activity in which The Save the Children Fund, in co-operation with other agencies, seeks to work constructively with government departments. As the Tung Tau matter demonstrates, if we cannot address the needs of a group who are demonstrably one of the most vulnerable yet least culpable, then we have a long way to go for all children in Hong Kong. P. G. BARKER Field director Save the Children Fund