Beat first 4 ingredients at medium speed with an electric mixer for 2 minutes. Stir in coconut and pecans.
Pour into 3 greased and floured 9 inch round cake pans.
Bake at 175 degrees C for 15-17 minutes or until a wooden pick inserted in centre comes out clean. Cool in pans on wire racks 10 minutes. Remove from pans, and cool completely on wire racks.
Sprinkle each cakes layer evenly with rum, if desired, let stand 10 minutes.
Cream Cheese Frosting: Beat cream cheese and butter at medium speed with an electric mixer until smooth. Gradually add icing sugar, beating until light and fluffy. Stir in vanilla and pecans. Frost cake when completely cooled.
Spread cream cheese frosting between layers and on top and sides of cake. Chill 2 hours before slicing.