JYJ member Jaejoong is causing waves in the Japanese Twittersphere. He tweeted yesterday, "I'm not forgetting Japanese so please study Korean hard as well." It's reported that 20 minutes after his post, "Korean" became the #1 keyword on Twitter Japan while Jaejoong himself was second. Netizens hearing the news commented, "Jaejoong's one statement made a huge effect," and "Hallyu star Jaejoong is impressive." Source + Photo: Newsen