The Schwarz-Gelben have reportedly offered the 21-year-old a four-year contract until 2006 after the keeper became unhappy at playing understudy to Georg Koch at the Betzenberg.
Werder Bremen were keeping tabs on the young custodian but Dortmund have apparently won the race for his signature and the arrival of Weidenfeller is sure to put a question mark over the future of Jens Lehmann in North West Germany.
"A conversation with Matthias Sammer (Dortmund coach) proved decisive," admitted Weidenfeller.
