Preheat oven to 375 degrees.
Grease and flour 10 inch tube pan or bundt pan
In a medium size bowl, sift together the flour and baking powder, set aside
In a large mixing bowl, beat together the butter and cream cheese until well blended.
Whip sugar, eggs, and lemon rind until mixture is light and fluffy.
Stir in flour/baking powder into the butter mixture
Stir in the poppy seeds.
Spoon the batter into the prepared pan and bake until the cake is a light golden brown and springs back firmly when pressed, 55-60 minutes. Watch carefully, I found it took less than the 55 minutes to bake (~45 minutes)
Cool for 15 minutes in the pan, then invert onto a wire rack to cool.
Drizzle the rum over the cake slowly allowing rum to permeate cake
Transfer to a cake plate or cake stand, cover, and let stand a couple of hours before serving
Serve with vanilla ice cream or fresh berries