In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in vanilla. In a small bowl, combine bananas and pineapple.
Combine the flour, baking soda, cinnamon and salt; add to the creamed mixture alternately with banana mixture, beating well after each addition. Fold in coconut and walnuts.
Fill paper-lined muffin cups two-thirds full. Bake at 350° for 20-25 minutes or until a toothpick inserted near the center comes out clean. Cool for 10 minutes before removing from pans to wire racks to cool completely.
In a small bowl, beat cream cheese and butter until fluffy. Add confectionersâ sugar and vanilla; beat until smooth. Frost cupcakes. Yield: about 2 dozen.