Combine first 5 ingredients in a large heavy-duty zip-top plastic bag, reserving 1/2 cup of the mixture. Place pheasants in the remaining mixture in the plastic bag. Seal and chill at least 30 minutes.
Remove pheasants from marinade, discarding marinade in bag. Sprinkle with salt; brown pheasants on all sides in hot oil in a large roasting pan over medium-high heat.
Bake at 400° for 40 to 50 minutes. Remove pheasants from roasting pan; keep warm.
Bring reserved marinade to a boil in roasting pan over high heat, stirring to loosen browned particles. Stir in red wine, and cook 4 to 5 minutes or until liquid is reduced by half. Pour mixture through a fine wire-mesh strainer in a medium saucepan, discarding solids. Add dried plums and broth, and simmer 5 minutes; remove from heat, and stir in butter until melted.
Cut pheasants into quarters; place on serving platter. Drizzle with sauce and serve.
*Eight (1- to 1 1/2-pound) Cornish hens make a delicious substitution for the pheasants.