Darren Collins hit a post in the 5th minute and Tommy Langley wasted 2 good chances for The Ducks before the visitors took a surprise 33rd minute lead when Jimmy Tibbs sent a great through ball to Dean Parratt who finished from a tight angle.
United's equaliser came in the 80th minute when Daggers keeper Dave Morgan and defender Pat Staunton got into a terrible muddle with a back pass and Collins nipped in to score.
Then in the 3rd minute of stoppage time, Daggers should have won it when Leo West got clear from what looked to be an offside position but with only Ducks keeper Tim Garner to beat, he stubbed his shot well wide.