Benin surrendered a two-goal lead as Mozambique fought back with goals from Almiro Lobo and Carlos Goncalves to claim a point in the Group C clash.
The Mambas trailed to two early goals and looked set for a heavy defeat before forcing their way back into the game and prompting the 55th-minute error from Benin keeper Yoann Djidonou.
Djidonou raced from his goal to kick a through-ball into touch but a quick throw-in found Domingues who squared for Goncalves to slot the ball home with the keeper still running back into his box.
Djidonou's opposite number Rafael Kapango was at fault for the opener when he tripped Razak Omotoyossi in the box, allowing the same player to pick himself up and give Benin a 14th lead from the spot.
It got worse for Mozambique in the 20th minute when Omotoyossi met a cross from the left by Stephane Sessegnon and Dario Khan's attempted challenge sent the ball into the net for an own goal.
But just as Benin seemed set to seize control Djidonou flapped at a 29th minute
corner allowing Almiro Lobo to head home and give the group minnows a chance of
salvaging something from the game.
Benin started the second half well with Khan successfully defending a chance
for Omotoyossi while at the other end Mozambique veteran Tico-Tico rolled the
ball home after being declared offside.
Djidonou's glaring error then gifted an equaliser for Mozambique for a goal
which maintained both sides' unwanted records of never having won a match in the
African Nations Cup finals.