He was initially only scheduled to spend three months with the Italian outfit during the Major League Soccer off-season but extended his time until the end of the Serie A campaign.
He returned to LA Galaxy during the summer and will feature for them in the upcoming MLS play-offs before his anticipated return to Milan.
The Serie A side have made an unconvincing start to their season after the departures of manager Carlo Ancelotti, who is now at Chelsea, and playmaker Kaka, who joined Real Madrid in June.
However, Seedorf said the expected return of Beckham would aid the team.
Capello reveals Beckham ultimatum
"He was already a great help last year," stated the 33-year-old former Dutch international, who is the only player to win the Champions League with three different clubs - Ajax, Real Madrid and Milan.
"I'm very happy that he will be back again as we also became friends.
"We all know Beckham. The most important thing is that he is going to bring a lot of professionalism and personality with his game.
"His specific qualities are well known but what we need in a team of AC Milan players are those who are not afraid to play the big games and not afraid to take responsibility - and David is such a player."
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