During several innacuretaly determinable situations we had sudden crashes of Elexis during work. These however were only occuring on OS X.
After some research I found out that the bug is caused by a NPE in the SWT List element every time one removed the last element of the list. I filed a respective bug on the Eclipse Bugtracker
Now I found the reason for this stuff to happen and it is entirely due to the MouseDown on the MenuItem entry not being followed by a MouseUp event. If you are interested in a sample application to demostrate the bug take a look at https://github.com/col-panic/generic-stuff
The bug was finally tracked down, and a patch was created according to my findings from Silenio Quarti – NICE!