The 31-year-old only completed his loan move from Manchester City to the Stadium of Light a day after the closure of the January window because of problems with the club's communications network on Monday.
However, he is relishing the chance to prove himself once again after managing only six appearances for City this season, and only two of those in the Barclays Premier League.
Benjani told Sunderland's official website, www.safc.com: "It feels really great to be here and I am very happy with my decision. Sunderland is a good club.
"I am feeling fit and well and ready to play. I have been injured for a long time in the past, but I have recovered well.
"Now I have a chance to play regularly here and hopefully I will get the time on the pitch.
"The season for them is okay, but not so much for me as I have not been playing. As a player, I need to play and that has been frustrating.
"As a striker, I always want to score in every game. There are some good players here and I am looking forward to playing with them."
Full story tomorrow