I'm stupid sometime...
Code:
nohup /volume1/@appstore/JavaManager/Java/bin/java -Djava.awt.headless=true -jar /volume1/@appstore/jdownloader/JDownloader.jar &
so like indicated, I have install Java (jdk-7u71-linux-i586.tar.gz) and now, it's better
Code:
RedAkStation> ps | grep -i JDownloader
23067 root 1232m S /volume1/@appstore/JavaManager/Java/jre/bin/java -Djava.awt.headless=true -jar JDownloader.jar -afterupdate
23240 root 3816 S grep -i JDownloader
but how to use JDownloader ?