Beat eggs and stir in raisins and vanilla. Refrigerate for at least 1 hour.
Preheat oven to 180 C / Gas 4.
Cream together margarine, dark brown soft sugar and caster sugar until light and fluffy. Combine flour, bicarbonate of soda, salt and cinnamon; stir into the sugar mixture. Mix in raisins and eggs, then stir in oats and walnuts. Roll dough into walnut sized balls and place 5cm apart on ungreased baking trays.
Bake for 10 to 12 minutes in preheated oven or until edges are golden. Cool on wire racks.