Set aside streusel packet from muffin mix. In large bowl, stir muffin mix, ginger and nutmeg. In medium bowl, beat eggs with fork. Stir in orange juice concentrate, milk and oil. Stir in carrots and 1/2 cup of the walnuts. Using rubber spatula, fold wet ingredients into dry ingredients just until moistened (batter may be slightly lumpy; do not overmix).