Put oven rack in middle position and preheat oven to 325º F.

Sprinkle ribs evenly with salt.

Bring all other ingredients to a boil in a roasting pan over moderately high heat, stirring until sugar is dissolved. Add ribs in one layer using tongs, turning to coat, and cover pan tightly with foil.

Braise ribs in oven until very tender, about 2 hours.

Before serving: Reduce oven temperature to 200º F.

Transfer ribs to a baking dish, arranging them in one layer, and keep warm in oven.

Skim fat from cooking liquid if desired, then make glaze by boiling liquid, uncovered, and stirring occasionally, until syrupy and reduced to about 3/4 cup - about 15 min.

Brush glaze generously on ribs.