FLT CREW OF B757-200 RECEIVE FINAL WT CHK REFLECTING PREVIOUS DEP.

Narrative

OUR FLT DEPARTED WITHOUT OUR FINAL WT MANIFEST. WE HAD JUST DIVERTED TO MKE ON A FLT FROM SFO TO ORD DUE TO WX. AS ONE MIGHT IMAGINE; WE WERE VERY BUSY AND TRYING TO GET OUR PAX TO THEIR DEST AND CONNECTIONS. WE DID NOT REALIZE UNTIL AFTER DEP THAT WE HAD LEFT WITHOUT THE FINAL WT MANIFEST. IN FACT; WE THOUGHT WE HAD IT BEFORE DEP. THE MANIFEST THAT PRINTED ON THE COCKPIT PRINTER SAID 'FINAL WT MANIFEST;' AND SO WHEN WE DID OUR SOP'S WE KNEW THAT THE DOCUMENT WE WERE USING SAID THAT IT WAS THE FINAL WT MANIFEST. HOWEVER; LATER WE INSPECTED IT AND BELOW THE TITLE WAS OUR FLT NUMBER FOLLOWED BY SFOMKE. WHAT I DO NOT UNDERSTAND IS WHY THIS DOCUMENT EXITED THE PRINTER AND HAD THE 'FINAL WT MANIFEST' TITLE ON IT WHEN IT WAS ACTUALLY THE FINAL WT MANIFEST FOR OUR PREVIOUS FLT SEGMENT. I GUESS THIS WAS WHAT WE COULD CALL A 'GOTCHA' THAT WE MISSED. MY SUGGESTION IS THAT NOTHING GETS AUTOMATICALLY PRINTED IN THE COCKPIT PRIOR TO DEP THAT SAYS 'FINAL WT MANIFEST' THAT IS NOT THE FINAL WT MANIFEST FOR THAT PARTICULAR FLT. BY THE WAY; THE ACARS HAD BEEN PROGRAMMED PROPERLY.