Outsiders Zambia hold Tunisia
Dutch-based forward Jacob Mulenga gave Zambia a shock lead but Tunisia, champions in 2004, levelled before halftime through Zouheir Dhaouadi in the Group D match.
Gabon, who pulled off a major surprise with their 1-0 win over Cameroon in the first-half of a double header in Lubango, lead the group with three points.
Zambia, who have gone out in the first round in their last five Nations Cup appearances, made a lively start and went ahead after 19 minutes when Mulenga provided a clinical finish after the ball was slipped to him by James Chamanga.
Tunisia levelled five minutes before halftime when Youssef Msakni burst into the Zambia penalty and passed the ball to Dhaouadi who fired into the roof of the net.
Zambia created the better openings in the second half.
Kampamba Chintu wasted a chance by misdirecting a header after several players beat the offside trap at a free kick, then Rainford Kalaba headed wide at the far post and Malenga sent a dangerous effort into the side-netting.
In the last minute, Kalaba had a fierce free kick parried by Aymen Mathlouthi and Chris Katongo headed over from the rebound.