JYJ member Jaejoong is planning to give fans a special surprise on his birthday. 

According to Jaejoong's agency C-JeS Entertainment, "Kim Jaejoong is planning on prereleasing a song from his upcoming second album on Jan. 26, his birthday." 

The pre-release song is titled "Did You Know That?" and is meant to be a gift for fans who have been with him ever since he began his military service last year.

"Did You Know That?" is a pop track that combines Jaejoong's unique vocals with lyrics about a man who has fallen in love.

Jaejoong's upcoming album includes tracks from a variety of genres, including hard rock, British pop, blues, ballads, and more. In addition, the album will contain a total of 12 tracks. 

Out of all the songs on the album, Jaejoong composed two of them himself and wrote lyrics for nine of the tracks.

Preorders for Jaejoong's second album begin on Jan. 26. However, the album will be officially released on Feb. 12.