Caldwell spent 2010 as the assistant linebackers coach under Bill Shuey, and Zordich was a defensive quality-control coach. Both Caldwell and Zordich are former Eagles -- Caldwell from 1998-2001 and Zordich from 1994-1998 -- and played 11 and 12 years in the league, respectively.
While neither guy has a ton of coaching experience, both guys have extensive playing experience and will have the trust of the players they're coaching because of it. Their experience will also be invaluable for Juan Castillo, who will be entering his first season as a defensive coordinator.
Neither player was ever really Pro Bowl-caliber, but both guys were key contributors during their careers and made a lot of plays because of their football acumen. Right off, that has the makings of a good coach because, as the old saying goes, "Those who can't do, teach."
The only question left to be answered is what exactly Zordich's title means. He is specifically listed as the Eagles secondary/safeties coach, which could mean the team still intends on bringing in a cornerbacks coach and setting something up similar to the Green Bay Packers coaching staff.
In fact, according to Jeff McLane of the Philadelphia Inquirer, that's exactly what the team is doing.
A name being mentioned is former San Francisco 49ers secondary coach Johnnie Lynn, but there isn't a ton of weight behind that and it's just a rumor at this point.
Lynn played defensive back in the NFL with the New York Jets in 1979, then in 1980-1986 before becoming a coach with the Jets and most recently the 49ers.
Assuming the team will hire a cornerbacks coach, there are only a few positions left to fill on the defensive coaching staff. The team will still need a couple quality-control coaches, which could be filled by a former player like Seth Joyner who has shown interest in joining the Eagles staff, and there is still a vacancy for a special teams quality-control coach after Jeff Nixon left to coach the Miami Dolphins running backs.
UPDATE: Adam Caplan of FOXSports.com is also reporting Zordich will only coach the safeties, so the team fully intends to hire a cornerbacks coach.