The former Monaco, Milan, Rangers and England striker was made player-manager at Boothferry Park in July 1997, but after just 17 wins he was sacked in November 1998.
Since then he has failed to hold down a job, but will now take over coaching duties with forwards at Dundee FC. New director Giovanni di Stefano will pay his wages at Dens Park.
Manager Jim Duffy says he is "delighted" at the news.