Application: umbrello (2.4.5)
KDE Platform Version: 4.4.5 (KDE 4.4.5)
Qt Version: 4.6.2
Operating System: Linux 2.6.32-28-generic-pae i686
Distribution: Ubuntu 10.04.2 LTS

-- Information about the crash:
When I create a sequence diagram with umbrello, and add two icons on the diagram, when I click on "undo" button, umbrello crashes

 -- Backtrace:
Application: Umbrello UML Modeller (umbrello), signal: Segmentation fault
[KCrash Handler]
#6  0x0865c9f2 in Q3CanvasItem::update (this=0xac58514, colour=...) at /usr/include/qt4/Qt3Support/q3canvas.h:164
#7  UMLWidget::setLineColorcmd (this=0xac58514, colour=...) at ../../../umbrello/umbrello/widgets/umlwidget.cpp:456
#8  0x0861522b in Uml::CmdChangeLineColor::undo (this=0xac2d2e8) at ../../../umbrello/umbrello/cmds/widget/cmd_changeLineColor.cpp:49
#9  0xb69fd427 in QUndoStack::undo (this=0xa68e068) at util/qundostack.cpp:659
#10 0xb6a249f3 in QUndoStack::qt_metacall (this=0xa68e068, _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0xbfd7d698) at .moc/release-shared/moc_qundostack.cpp:105
#11 0xb7172e22 in KUndoStack::qt_metacall (this=0xa68e068, _c=QMetaObject::InvokeMetaMethod, _id=12, _a=0xbfd7d698) at ./kundostack.moc:64
#12 0xb60a8c9a in QMetaObject::metacall (object=0xa68e068, cl=QMetaObject::InvokeMetaMethod, idx=12, argv=0xbfd7d698) at kernel/qmetaobject.cpp:237
#13 0xb60b73d5 in QMetaObject::activate (sender=0xa694c48, m=0xb6c16d58, local_signal_index=1, argv=0xbfd7d698) at kernel/qobject.cpp:3293
#14 0xb62e7bd9 in QAction::triggered (this=0xa694c48, _t1=false) at .moc/release-shared/moc_qaction.cpp:263
#15 0xb62e9dcc in QAction::activate (this=0xa694c48, event=QAction::Trigger) at kernel/qaction.cpp:1255
#16 0xb62eb698 in QAction::event (this=0xac58514, e=0x5) at kernel/qaction.cpp:1181
#17 0xb62ee4dc in QApplicationPrivate::notify_helper (this=0xa4e7f70, receiver=0xa694c48, e=0xbfd7db38) at kernel/qapplication.cpp:4300
#18 0xb62f505e in QApplication::notify (this=0xbfd7ea10, receiver=0xa694c48, e=0xbfd7db38) at kernel/qapplication.cpp:3704
#19 0xb70ca40a in KApplication::notify (this=0xbfd7ea10, receiver=0xa694c48, event=0xbfd7db38) at ../../kdeui/kernel/kapplication.cpp:302
#20 0xb60a3a3b in QCoreApplication::notifyInternal (this=0xbfd7ea10, receiver=0xa694c48, event=0xbfd7db38) at kernel/qcoreapplication.cpp:704
#21 0xb633034d in QCoreApplication::sendEvent (this=0xa4e801c, e=0xbfd7dfb4) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#22 QShortcutMap::dispatchEvent (this=0xa4e801c, e=0xbfd7dfb4) at kernel/qshortcutmap.cpp:879
#23 0xb633215e in QShortcutMap::tryShortcutEvent (this=0xa4e801c, o=0xa7f3ed0, e=0xbfd7dfb4) at kernel/qshortcutmap.cpp:364
#24 0xb62f6e43 in QApplication::notify (this=0xbfd7ea10, receiver=0xa7f3ed0, e=0xbfd7dfb4) at kernel/qapplication.cpp:3746
#25 0xb70ca40a in KApplication::notify (this=0xbfd7ea10, receiver=0xa7f3ed0, event=0xbfd7dfb4) at ../../kdeui/kernel/kapplication.cpp:302
#26 0xb60a3a3b in QCoreApplication::notifyInternal (this=0xbfd7ea10, receiver=0xa7f3ed0, event=0xbfd7dfb4) at kernel/qcoreapplication.cpp:704
#27 0xb62ef2be in QCoreApplication::sendSpontaneousEvent (receiver=0xa7f3ed0, event=0xac58514) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#28 qt_sendSpontaneousEvent (receiver=0xa7f3ed0, event=0xac58514) at kernel/qapplication.cpp:5279
#29 0xb63a8d90 in QKeyMapper::sendKeyEvent (keyWidget=0xa7f3ed0, grab=false, type=QEvent::KeyPress, code=90, modifiers=..., text=..., autorepeat=<value optimized out>, count=<value optimized out>, 
    nativeScanCode=25, nativeVirtualKey=122, nativeModifiers=20) at kernel/qkeymapper_x11.cpp:1861
#30 0xb63ab2f5 in QKeyMapperPrivate::translateKeyEvent (this=0xa511e10, keyWidget=0xa7f3ed0, event=0xbfd7e67c, grab=5) at kernel/qkeymapper_x11.cpp:1831
#31 0xb637e757 in QApplication::x11ProcessEvent (this=0xbfd7ea10, event=0xbfd7e67c) at kernel/qapplication_x11.cpp:3394
#32 0xb63ae60a in x11EventSourceDispatch (s=0xa4eb1a8, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#33 0xb54055e5 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#34 0xb54092d8 in ?? () from /lib/libglib-2.0.so.0
#35 0xb54094b8 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#36 0xb60cf5d5 in QEventDispatcherGlib::processEvents (this=0xa4cac20, flags=...) at kernel/qeventdispatcher_glib.cpp:412
#37 0xb63ae135 in QGuiEventDispatcherGlib::processEvents (this=0xa4cac20, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#38 0xb60a2059 in QEventLoop::processEvents (this=0xbfd7e974, flags=) at kernel/qeventloop.cpp:149
#39 0xb60a24aa in QEventLoop::exec (this=0xbfd7e974, flags=...) at kernel/qeventloop.cpp:201
#40 0xb60a669f in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#41 0xb62ee577 in QApplication::exec () at kernel/qapplication.cpp:3579
#42 0x086ac645 in main (argc=1, argv=0xbfd7ebc4) at ../../../umbrello/umbrello/main.cpp:111

Reported using DrKonqi