The midfielder, 30, was deemed surplus to requirements in May after one season at Roots Hall in which he impressed before suffering a knee injury in February, curtailing his campaign.
However, he may yet have a future with the League Two club.
Manager Paul Sturrock told Southend's official website: "Kalala is back for the physio to have a look at him and asses his fitness. He had a knee injury last season and he still has some work to do but who knows what will happen.
"His knee is an aspect as it is not totally back to normal yet.
"But he played in 30 games last season, which were 15 wins, five draws and 10 defeats. That shows the influence he had on the team, but we will have to wait and see if anything will happen."