The announcement came hours before Serbian champions Partizan host Armenians FC Shirak in the return leg of their Champions League second qualifying round, with the first leg having ended in a 1-1 draw.
"After negotiations that lasted all day on Tuesday, the two parties hammered out the contract details today and the player will be eligible to play for Partizan in the Champions League should the club advance into the third qualifying round," Partizan said .
The 32-year-old defensive midfielder had two patchy seasons at United from 2003 to 2005, failing to break into the first team before moving to Aston Villa where he made just 11 league appearances from 2005 to 2007 and was loaned to Championship side Burnley.
Djemba Djemba spent one season at Qatar SC and reinvigorated his career at Danish top-flight outfit Odense, scoring three goals in 109 league games from 2008 to 2012 before joining Hapoel Tel Aviv last year.
He was a member of the Cameroon team who won the 2002 African Nations Cup and played for his country in the World Cup the same year.
Internet forums suggest many Partizan fans see him as an ideal replacement for stalwart Milan Smiljanic, who has joined Turkish first division side Genclerbirligi after helping the Serbian champions to a record sixth successive league title.