don't know the root of the problem yet:

org.eclipse.emf.common.util.wrappedexception: an exception was ignored during command execution
at org.eclipse.emf.common.command.basiccommandstack.handleerror(basiccommandstack.java:287)
at org.eclipse.emf.transaction.impl.abstracttransactionalcommandstack.handleerror(abstracttransactionalcommandstack.java:125)
at org.eclipse.emf.transaction.impl.abstracttransactionalcommandstack.execute(abstracttransactionalcommandstack.java:229)
at org.unicase.workspace.util.unicasecommand.run(unicasecommand.java:45)
at org.unicase.ui.unicasecommon.diagram.part.modeldiagrameditor.dosave(modeldiagrameditor.java:117)
at org.unicase.ui.unicasecommon.diagram.part.modeldiagrameditor$1.focuslost(modeldiagrameditor.java:90)
at org.eclipse.swt.widgets.typedlistener.handleevent(typedlistener.java:137)
at org.eclipse.swt.widgets.eventtable.sendevent(eventtable.java:84)
at org.eclipse.swt.widgets.display.sendevent(display.java:3543)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1250)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1273)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1254)
at org.eclipse.swt.widgets.control.sendfocusevent(control.java:2860)
at org.eclipse.swt.widgets.canvas.sendfocusevent(canvas.java:62)
at org.eclipse.swt.widgets.display.checkfocus(display.java:574)
at org.eclipse.swt.widgets.shell.makefirstresponder(shell.java:1006)
at org.eclipse.swt.widgets.display.windowproc(display.java:4757)
at org.eclipse.swt.internal.cocoa.os.objc_msgsendsuper(native method)
at org.eclipse.swt.widgets.widget.callsuperboolean(widget.java:230)
at org.eclipse.swt.widgets.widget.becomefirstresponder(widget.java:295)
at org.eclipse.swt.widgets.control.becomefirstresponder(control.java:614)
at org.eclipse.swt.widgets.text.becomefirstresponder(text.java:297)
at org.eclipse.swt.widgets.display.windowproc(display.java:4539)
at org.eclipse.swt.internal.cocoa.os.objc_msgsendsuper(native method)
at org.eclipse.swt.widgets.widget.callsuperboolean(widget.java:250)
at org.eclipse.swt.widgets.widget.makefirstresponder(widget.java:993)
at org.eclipse.swt.widgets.shell.makefirstresponder(shell.java:1005)
at org.eclipse.swt.widgets.display.windowproc(display.java:4757)
at org.eclipse.swt.internal.cocoa.os.objc_msgsend_bool(native method)
at org.eclipse.swt.internal.cocoa.nswindow.makefirstresponder(nswindow.java:171)
at org.eclipse.swt.widgets.control.forcefocus(control.java:1241)
at org.eclipse.swt.widgets.control.setfocus(control.java:3219)
at org.eclipse.ui.internal.views.log.logview.setfocus(logview.java:1082)
at org.eclipse.ui.internal.partpane.setfocus(partpane.java:332)
at org.eclipse.ui.internal.workbenchpage$3.run(workbenchpage.java:626)
at org.eclipse.core.runtime.saferunner.run(saferunner.java:42)
at org.eclipse.core.runtime.platform.run(platform.java:888)
at org.eclipse.ui.internal.workbenchpage.activatepart(workbenchpage.java:621)
at org.eclipse.ui.internal.workbenchpage.setactivepart(workbenchpage.java:3527)
at org.eclipse.ui.internal.workbenchpage.requestactivation(workbenchpage.java:3071)
at org.eclipse.ui.internal.partpane.requestactivation(partpane.java:279)
at org.eclipse.ui.internal.partpane.handleevent(partpane.java:237)
at org.eclipse.swt.widgets.eventtable.sendevent(eventtable.java:84)
at org.eclipse.swt.widgets.display.sendevent(display.java:3543)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1250)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1273)
at org.eclipse.swt.widgets.widget.sendevent(widget.java:1254)
at org.eclipse.swt.widgets.shell.setactivecontrol(shell.java:1235)
at org.eclipse.swt.widgets.control.sendmouseevent(control.java:2932)
at org.eclipse.swt.widgets.control.mouseevent(control.java:2146)
at org.eclipse.swt.widgets.composite.mouseevent(composite.java:730)
at org.eclipse.swt.widgets.toolitem.mousedown(toolitem.java:554)
at org.eclipse.swt.widgets.display.windowproc(display.java:4653)
at org.eclipse.swt.internal.cocoa.os.objc_msgsendsuper(native method)
at org.eclipse.swt.widgets.widget.callsuper(widget.java:202)
at org.eclipse.swt.widgets.widget.windowsendevent(widget.java:1753)
at org.eclipse.swt.widgets.shell.windowsendevent(shell.java:1825)
at org.eclipse.swt.widgets.display.windowproc(display.java:4713)
at org.eclipse.swt.internal.cocoa.os.objc_msgsendsuper(native method)
at org.eclipse.swt.widgets.display.applicationsendevent(display.java:4285)
at org.eclipse.swt.widgets.display.applicationproc(display.java:4352)
at org.eclipse.swt.internal.cocoa.os.objc_msgsend(native method)
at org.eclipse.swt.internal.cocoa.nsapplication.sendevent(nsapplication.java:101)
at org.eclipse.swt.widgets.display.readanddispatch(display.java:3097)
at org.eclipse.ui.internal.workbench.runeventloop(workbench.java:2405)
at org.eclipse.ui.internal.workbench.runui(workbench.java:2369)
at org.eclipse.ui.internal.workbench.access$4(workbench.java:2221)
at org.eclipse.ui.internal.workbench$5.run(workbench.java:500)
at org.eclipse.core.databinding.observable.realm.runwithdefault(realm.java:332)
at org.eclipse.ui.internal.workbench.createandrunworkbench(workbench.java:493)
at org.eclipse.ui.platformui.createandrunworkbench(platformui.java:149)
at org.eclipse.ui.internal.ide.application.ideapplication.start(ideapplication.java:113)
at org.eclipse.equinox.internal.app.eclipseapphandle.run(eclipseapphandle.java:194)
at org.eclipse.core.runtime.internal.adaptor.eclipseapplauncher.runapplication(eclipseapplauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.eclipseapplauncher.start(eclipseapplauncher.java:79)
at org.eclipse.core.runtime.adaptor.eclipsestarter.run(eclipsestarter.java:368)
at org.eclipse.core.runtime.adaptor.eclipsestarter.run(eclipsestarter.java:179)
at sun.reflect.nativemethodaccessorimpl.invoke0(native method)
at sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:39)
at sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:25)
at java.lang.reflect.method.invoke(method.java:592)
at org.eclipse.equinox.launcher.main.invokeframework(main.java:559)
at org.eclipse.equinox.launcher.main.basicrun(main.java:514)
at org.eclipse.equinox.launcher.main.run(main.java:1311)
caused by: org.eclipse.emf.transaction.rollbackexception:
at org.eclipse.emf.transaction.impl.transactionimpl.commit(transactionimpl.java:405)
at org.eclipse.emf.transaction.impl.transactionalcommandstackimpl.doexecute(transactionalcommandstackimpl.java:70)
at org.eclipse.emf.transaction.impl.abstracttransactionalcommandstack.execute(abstracttransactionalcommandstack.java:165)
at org.eclipse.emf.transaction.impl.abstracttransactionalcommandstack.execute(abstracttransactionalcommandstack.java:219)
... 81 more
