Albion's hopes of snatching a play-off place suffered a severe setback as they were held again by the League leaders.
A Paul Watson free-kick in the first half was cancelled out by an almost identical goal from Steve Thompson for Rotherham shortly afterwards.
Referee Paul Danson allowed the match to go ahead on a boggy Withdean pitch folowing a morning inspection.
Fans helped with the mopping up operation and their efforts looked like being rewarded when Watson put the Seagulls ahead on 25 minutes before another sell-out crowd of 5,805.
The set piece specialist curled in a delightful free-kick from 20 yards, his fifth of the season.
Albion deserved their lead at that stage after their lively opening
But Thompson equalised eight minutes later with a low free-kick from the same range.
Rotherham were happy to settle for a point in the second half.
Albion manager Micky Adams made three substitutions, bringing on Scott Ramsay, Warren Aspinall and Rod Thomas in place of Paul Brooker, Martin Ling and Darren Freeman in a bid to clinch a crucial win.
Ramsay and Aspinall both went close late on.
But Albion's third draw on the trot, and Rotherham's fourth, suited the visitors much better.
Adams believes the Seagulls, now unbeaten for ten games, still have a chance if they win their last four, starting with next Saturday's trip to York.
For lots more on the Albion, don't miss this weekend's Sports Argus. Reaction and pictures from the Rotherham game can be found in Monday's Argus.
Converted for the new archive on 30 June 2000. Some images and formatting may have been lost in the conversion.
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