B737 ENCOUNTERS CONFUSION WITH ATC DSCNT CLRNC INTO OAK.

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DURING THE MARVN 1 ARR INTO OAK WE HAD CLRNC TO CROSS VOLTA AT 13000 FT. BEFORE XING VOLTA NORCAL APCH CLRED US 'AFTER VOLTA DIRECT CATTY; CROSS 28 MI E OF CATTY AT 8000 FT.' I LOADED THE CLRNC INTO THE FMC TO DETERMINE OUR DSCNT PROFILE. WE NEEDED TO HURRY DOWN AS WE ONLY HAD 12 MI TO LOSE 5000 FT. AT THAT POINT; THE CAPT WENT OFF COM #1 TO TELL THE FLT ATTENDANTS TO SECURE THE CABIN. I WAS SLOWING TO 250 KTS AND BEGAN DSNDING THROUGH 10000 FT. AT AROUND 9600 FT; THE CTLR CASUALLY STATED 'COMPANY NUMBER; I NEED YOU AT 10000 FT.' I RESPONDED 'ROGER; 10000 FT; COMPANY NUMBER.' I THEN ASKED 'IS THAT A NEW CLRNC RATHER THAN THE 28 MI E OF CATTY AT 8000 FT?' THE CTLR RESPONDED 'MY APOLOGIES IF THAT'S WHAT I GAVE YOU EARLIER. I NEED YOU AT 10000 FT.' LATER; THE CTLR SAID 'MY APOLOGIES COMPANY; NOW CROSS CATTY AT 8000 FT AND CONTACT NORCAL ON XXX.X.' THE REST OF THE FLT WAS UNEVENTFUL. THE CAPT AND I BOTH BELIEVE THIS TO BE A SIMPLE CASE OF AN ATC MISSPOKEN CLRNC AND WAS RESOLVED WITHOUT ANY CONFLICTS OR PROBS.