As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PSP - CREW REPORTED ODOR AND SMOKE IN THE CABIN. EMERGENCY DECLARED FLIGHT RETURNED PSP LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. PLACARD AUXILIARY POWER UNIT AND ACCOMPLISHED PACK BURN. REPLACED APU AT DFW ON 05/15/2012. SYSTEM GROUND CHECK NORMAL OPERATION.