ACR ON TKOF ROLL SEES ACR WITH IDENTICAL CALL SIGN FAIL TO HOLD SHORT OF RWY. TKOF ABORTED.

Narrative

APCHING RWY 25R; TWR CLRED US (ACR AB XYZ) FOR TKOF. WE BEGAN OUR TKOF ROLL WHEN WE HEARD THE TWR ADVISE ACR CB XYZ TO HOLD SHORT OF 25R AFTER LNDG. HE WAS LNDG ON 25L. THE FO WAS MAKING THE TKOF AND BECAUSE OF THE COMMON FLT NUMBER HE HESITATED VERY BRIEFLY ADVANCING PWR LEVERS UNTIL I MENTIONED THE XMISSION WAS NOT FOR US. AS WE WERE ACCELERATING; I NOTICED CB XYZ TURNING OFF 25L AT A FAIRLY RAPID SPD AND THOUGHT HE MIGHT NOT BE STOPPING SHORT OF OUR RWY. I WATCHED HIM AND AT ABOUT 115 KTS IT WAS CLR TO ME CB XZY WASN'T STOPPING; SO I ABORTED THE TKOF. AT ABOUT THE SAME MOMENT CB XYZ MADE AN ABRUPT STOP WITH HIS NOSE SLIGHTLY EXTENDING ONTO RWY 25R. WE STOPPED SHORT OF HIS POS AND WITHOUT INCIDENT. CB XYZ COMMENTED TO TWR THAT THEY THOUGHT THEY HAD BEEN CLRED TO CROSS RWY 25R. MY DISCUSSION WITH THE TWR DID NOT INDICATE ANY MISTAKE OR MISUNDERSTANDING ON OUR PART; HOWEVER; THE COMMON FLT NUMBER CERTAINLY CAUSED US SOME HESITATION BY WAY OF POSSIBLE MISUNDERSTANDING. THIS CERTAINLY COULD HAVE BEEN RESPONSIBLE FOR CB XYZ MISTAKE. THERE IS SIGNIFICANT POTENTIAL FOR MISUNDERSTANDINGS AND ERRORS WITH COMMON OR SIMILAR FLT NUMBERS ON FREQ. SOME TYPE OF MONITORING AND CONTACT WITH THE AFFECTED AIR CARRIERS INVOLVED SHOULD BE DONE BY THE ATC FACILITIES.