Combine cabbage and celery; set aside.
Place eggs and sugar in a medium saucepan; beat well. Combine mustard, salt, and pepper; add to egg mixture. Add butter, and slowly stir in vinegar. Cook over low heat, stirring constantly, until mixture is thickened. Remove from heat; chill.
Add whipping cream to chilled mixture, stirring well. Pour sauce over cabbage mixture; toss well. Cover and chill.