Bug Report - Java error locking entire pc

Not sure why this is happening but sometimes when a new game starts, a small window pop-ups rapidily one after another saying java ui errors. The problem is it pops up with non stop windows and the only way to make it stop is to reboot your pc. You can't get to task manager because the xmage program keeps opening more and more windows.
Anyone else suffering from this?
Anyone else suffering from this?