How do I remove OpenJDK without losing JDownloader?

view story

http://askubuntu.com – I recently installed Sun's Java because of performance issues running Minecraft. When I try to remove the OpenJDK packages by sudo apt-get purge openjdk* however, the JDownloader package is being removed as well. If I try to remove all OpenJDK-7 packages one by one, OpenJDK-6 is being installed instead. IMHO there should be a way to satisfy JDownloader's dependencies for a Java runtime environment with Sun's version. Is there any way to keep JDownloader while completely removing the opensource Java versions? (HowTos)