The USA international, 26, is yet to make his debut in the red and white of the Addicks after suffering ligament damage just before the 2006 World Cup.
He played the first half of a reserves game in November but aggravated the injury again and Wayne Diesel, head of Charlton's medical department said 'We are not going to rush things'.
When Gibbs finally makes his debut, he could be a Championship player due to Charlton's procarious position in the top flight.