Preheat oven to 400°. Combine chives, mayonnaise, and Dijon mustard. Cut Hawaiian rolls in half horizontally, cutting to, but not through, other side. Place rolls, cut sides up, on a baking sheet; bake at 400° for 5 minutes or until golden. Spread cut sides evenly with mayonnaise mixture. Divide ham evenly among bottoms of rolls. Cover with roll tops; cut into individual rolls.