The former Portsmouth man, 29, was a surprise mover as the January window shut but after initial reports that he had signed for City, it was suggested that his registration had not been completed in time.
But with the move now complete Benjani is eager to get started at City and said: "I am very happy to be a Manchester City player. Every player wishes to play for a big club. I enjoyed my time (at Portsmouth) but in life and in football you have to move on."
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