In a small bowl, just cover the pomegranate seeds with the Marsala. You may have to use more Marsala. Gently mix in the mint and set aside, covered, for 1 hour.
Season the birds inside and out with salt and pepper. Drain the pomegranate seeds and mint, reserving the liquid. Stuff the birds with the seeds, reserving a few for later, and the mint. Using a needle, truss each bird tightly so that the inner cavity is closed and sealed shut buy the 2 legs. Wrap each bird in a slice of pancetta, using your palms to press the pancetta tight against the bird.
Preheat the oven to 375 degrees F.
In an oven-proof saute pan, heat the olive oil. Add 3 sage leaves and cook 1 minute before adding the hens. Brown the birds on all sides over high heat until well browned, about 5 minutes. Lower the heat, and add the remaining sage leaves, and pomegranate seeds. Place the pan in the oven for 7 minutes. Remove the pan from the oven. Drizzle the hens with 3 tablespoons of the remaining Marsala and pat with 2 tablespoons of the butter. Baste the hens with the pan juices and return to the oven for 5 more minutes.
In a small saucepan, melt the remaining 6 tablespoons butter over low heat. Add the orange peel and saute gently for 5 minutes, stirring gently so that the peel absorbs the butter. Remove the sauteed peels from the heat.
Remove the hens from the oven and transfer them to a serving dish. Sprinkle the hens with the orange peel, and drizzle them with pan juices and any loose pomegranate seeds. Serve immediately.