Per Roch Kubatko on MASNSports.com, Zaun has been traded to the Rays for a player to be named later.
Zaun had to pass through waivers before he could be dealt.
Zaun signed a one-year deal over the winter with a team option for 2010, returning him to the organization that introduced him to the majors in 1995. He batted .244 with four homers and 13 RBIs in 56 games.
Moeller can mentor the young pitchers, and assist in Wieters' development, as Zaun did.
Unlike the Chad Bradford trade to Tampa Bay, the Orioles apparently will receive a player in return for Zaun. This isn't expected to be a cash transaction.