Slackware :: After Rebooting The Game Works, But On Ending The Game Several Notification Boxes Remain?

This game is Java based. After rebooting the game works, but on ending the game several notification boxes remain. If these boxes are not closed in the reverse order that the game opened them, it is no longer possible to close them. Only by killing the Java processes can these notifications be made to close. Also after playing the game, even if all these notifications are closed it is many times necessary to kill the Java process(es) in order to get the game to load again at a later time. I am currently using Slackware 1.30, but a similar problem has existed in several of the past releases.