What was found
AIRCRAFT WAS GROUNDED. DFW-MSY RETURNED DFW ACCOUNT FIRE INDICATION LIGHT. EMERGENCY WAS DECLARED, FLIGHT LANDED WITHOUT INCIDENT AND UNDERWEIGHT. AFTER TAKE OFF, TAIL COMPARTMENT TEMPERATURE HIGH LIGHT CAME ON. IT WAS INTERMITTENT AT FIRST GOING THROUGH 2000 FT. CAME ON STEADY UNTIL THRUST LEVERS WERE BROUGHT BACK TO CRUISE THRUST AT LEVEL OFF AT 4000 FT. LIGHT THEN WENT OUT. MAINTENANCE FOUND RT CROSSFEED DUCT LEAKING AT RT CROSSFEED VALVE AND DUCT MATING SURFACE. REMOVED AND REPLACED R/H CROSSFEED DUCT PER AMM 36-00-00, LEAK CHECK GOOD.