NMAC BTWN AN MLG AND AN SMT JET AT HIGH ALT CRUISE.

Narrative

LARGE LINE OF CB'S EXTEND FROM BOS; EWR; PHL; IAD; RIC; GSO. AT CRUISE AND PROCEEDING ALONG FILED RTE OF FLT DIRECT TO HPW. AT APPROX XA15Z WAS CTR ADVISED THAT THEY MAY HAVE TO CHANGE OUR ALT. SHORTLY AFTER; A RADAR VECTOR WAS GIVEN TO US TO THE NW TOWARDS LINE OF WX. WAS CTR ADVISED THAT HDG WON'T BE LONG AND BACK ON COURSE WOULD BE GIVEN SOON. WE ASSUMED THIS WAS FOR EWR SPACING AND TFC. WE WERE THEN GIVEN A R TURN DIRECT TO PTX FOR THE ARR INTO EWR. CTR WAS VERY BUSY WITH TFC AND LINE OF WX. AT APPROX 60 SW HPW; AND IN THE CLR; OUR TCASII GAVE US AN RA DSND FOLLOWED BY A CLB. I IMMEDIATELY DISCONNECTED AUTOPLT AND AUTOTHROTTLES AND FOLLOWED BOTH TCASII COMMANDS. WE HAD TARGET ON SCOPE AT OUR 1130 TO 1200 POS. DURING THE CLB MANEUVER I MADE A SLIGHT TURN TO THE R AWAY FROM TARGET; CLBING TO 29250 FT. WE FINALLY ACQUIRED A WHITE BUSINESS JET AT OUR 10 O'CLOCK POS (FALCON; CESSNA?) PASSING AND MISSING US AT FL290. WE ADVISED CTR OF OUR RA AND EVASIVE ACTION AND HOW CLOSE IT WAS. I KNOW THEY HAD THE CORPORATE JET UNDER THEIR CTL WHILE THE BUSINESS JET WAS CLBING TO FL290. WHEN THEY TURNED US BACK ON COURSE; THE SPACING WAS NOT SUFFICIENT I FEEL; BECAUSE OF THE CORPORATE JET HIGH RATE OF CLB TO FL290. THAT'S WHY WE GOT A DSND COMMAND FIRST; THEN WHEN OUR CONFLICTING TFC REACHED FL290; A CLB WAS COMMANDED. WE IMMEDIATELY RPTED THIS TO WAS CTR. I FEEL THE TCASII SYS SAVED OUR LIVES AND I WILL NEVER CUSS AT THIS SYS AGAIN!