Benjani will stay on loan at Sunderland until the end of the season.
The move was initially held up after Sunderland’s emails and faxes did not go through to the Football Association.
Bruce told the club’s official website: “He’s a big, strong, powerful centre-forward and one we’ve been tracking for a long time.
“I’m delighted that we’ve been able to bring him to the club, he’ll bring another dimension to our striking options and will be a great addition to the squad.”
