Pauleta, who came on for Uruguay's Carlos Bueno midway through the second half, struck in the 76th and 77th minutes for PSG, who are without a win in their last eight league outings.
PSG, ninth in Ligue 1, had opened the scoring through Bueno in the 30th minute.
The hosts, who claimed the scalps of Toulouse and Racing Strasbourg in the previous rounds, went closest to a goal when midfielder Edouard Cisse hacked the ball off the line with keeper Lionel Letizi beaten.
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