 Mumuni returned to Umea in September 2005 to play in an exhibition match against Fotbollgymnasiet to celebrate the opening of the club's Sports and Exhibition Centre.The Umea side consisted of players who had won promotion in 1996, with the players picked by Jorgen Sundberg, Umea's most-capped player.Ersboda SK were Mumuni's final club and he joined in 2002 at the age of 29.