Taken from Wikipedia:
" * [Unreleased] Dating on Earth
Dating on Earth involves all five members, but only Micky and Hero are main characters. The drama has Micky married to a high school teacher (Played by Seo Hyun Jin from the group M.I.L.K) with whom Hero falls in love. U-Know, Max, and Xiah play minor roles. The release date for the drama has not been confirmed, even though the drama was shot in 2006."
I'm wondering what's up with it as well. I've seen some of the making-of scenes floating around. I wonder why it's taken them two years and still no release?