In small skillet, heat oil over medium heat; cook onions, celery, gingerroot and garlic 3 to 5 minutes, stirring often, until onions are softened.
In medium bowl, combine onion mixture, chicken, mustard, lime juice, Worcestershire sauce, salt and pepper; set aside.
Keeping remaining pastry covered with damp tea towel, lay 1 sheet on work surface with long side towards you.
Brush one third of butter over sheet of pastry.
Fold short ends together like closing a book.
With sharp knife, cut pastry in half horizontally, then cut each half vertically into 3 even sized strips.
Place about 1 tablespoon (15 mL) of chicken mixture at bottom edge of 1 strip; form chicken mixture into log shape.
Fold in long sides of pastry strip, then roll up.
Place on un greased baking sheet.
Repeat until all pastry and chicken mixture are used.
Bake in 400F (200C) oven 15 minutes or until crisp and golden.
Serve hot.