Windows will lock if you instantiate a dialog and access the widgets in the parent window before the dialog is fully drawn. Under CDE, running the test case alone (no other windows up) causes the java application to lock up - mouse moves but no input is recorded. You are still able to change to the other workspaces, but as you add windows to the workspaces (terminals, calendar manager, mailtool, whatever), the more likely that all mouse input is ignored and your system is locked. Basically the busier CDE is, the more likely it is to lock up. This was first noticed on Openwin, and is more easily reproducible there, but has been seen on both OpenWin and CDE.