Cut chicken into bite-size strips.
In a medium bowl, stir together chicken, 2 tablespoons soy sauce and sherry (or chicken bouillon). Cover and chill for 30 minutes to 1 hour.
For sauce, in a small bowl stir together the orange juice concentrate, 2 tablespoons soy sauce, water, cornstarch and sugar. Set aside.
Add cooking oil to a wok or large skillet. Preheat over medium-high heat (add more oil if necessary during cooking). Stir-fry ginger in hot oil for 15 seconds. Add pepper strips; stir-fry for 1 to 2 minutes or until crisp-tender. Remove pepper strips from wok.
Add half of the chicken mixture to wok. Stir-fry for 2 to 3 minutes or until chicken is tender and no longer pink. Remove chicken from wok. Repeat with the remaining chicken mixture. Return all of the chicken to wok. Push chicken from center of wok.
Stir sauce; add to center of wok. Cook and stir until thickened and bubbly. Return pepper strips to wok. Add pineapple. Stir all ingredients together to coat. Cook and stir about 1 minute more or until mixture is heated through.
Serve immediately with hot rice. If desired, garnish with orange slices and rosemary.