Grilled Spicy Lamb Burgers

1 pound ground lamb
2 tablespoons chopped fresh mint leaves
2 tablespoons chopped fresh cilantro
2 tablespoons chopped fresh oregano
1 tablespoon garlic, chopped
1 teaspoon sherry
1 teaspoon white wine vinegar
1 teaspoon molasses
 1 teaspoon ground cumin
1/4 teaspoon ground allspice
1/2 teaspoon red pepper flakes
1/2 teaspoon salt
1/2 teaspoon ground black pepper
4 pita bread rounds
4 ounces feta cheese, crumbled

Preheat grill for medium heat.
Place the lamb in a large bowl, and mix with the mint, cilantro, oregano, garlic, sherry, vinegar, and molasses. Season with cumin, allspice, red pepper flakes, salt, and black pepper, and mix well. Shape into 4 patties.
Brush grill grate with oil. Grill burgers 5 minutes on each side, or until well done. Heat the pita pocket briefly on the grill. Serve burgers wrapped in pitas with feta cheese.