From the Kitchen of "Chef" Norm
(and Cornish Hens)
Source (if known): My friend Brent Helms enjoys a sauce on his duck and says this is outstanding.
He used it on cornish hens for 10 people in January 2012.
My notes:

Orange Sauce for Duck or Chicken

2/3 cup light brown sugar
2/3 cup sugar
2 tablespoons cornstarch
2 tablespoons grated orange peel
1/2 cup orange juice
1/4 to 1/2 cup orange liquer
1/2 teaspoon salt
1/2 orange skin, julienne stripped (peel of an orange with a vegetable peeler, slice peel thinly)

Combine sugars and cornstarch in a pot.  Mix.  Add rest of ingredients and bring to a boil,
then allow to simmer over low heat 3-4 minutes. Pour over duck or chicken (or cornish hens)