Melt butter in boiling water and add oatmeal. Set aside until cool.
Beat eggs with brown sugar, add vanilla extract and combine with oatmeal mixture.
Combine all dry ingredients, fold in coarsely chopped cherries & berries. Add wet mixture to dry, combining in swift strokes, until combined (batter will be lumpy).
Lightly oil muffin makers and add batter. Bake 20 to 25 minutes at 350° F (175° C).