Wash, halve and stone the fruit, but do not peel. Put into a preserving pan with water and lemon juice, cover and simmer gently for about 20 minutes or until fruit is tender. Add the sugar and cook over a low heat until dissolved. Bring to the boil and boil rapidly for 1 minute, stirring occasionally. Remove from the heat and stir in pectin. Cool for about 10 minutes so that the fruit is evenly distributed, then pour into hot sterilized jars and cover tightly.