Application that crashed: kolourpaint
Version of the application: 4.3.4 (KDE 4.3.4)
KDE Version: 4.3.4 (KDE 4.3.4)
Qt Version: 4.5.3
Operating System: Linux 2.6.30-2-amd64 x86_64
Distribution: Debian GNU/Linux unstable (sid)

What I was doing when the application crashed:
I used the text tool to place some text. Then I accidentally reactivated the text tool, and aborted it. Then decided to undo the placement of the original text. Upon hitting the undo button, Kolourpaint crashed.

 -- Backtrace:
Application: KolourPaint (kolourpaint), signal: Segmentation fault
[KCrash Handler]
#5  0x0000000000443678 in kpDocument::setSelection (this=0xee6020, selection=...) at ../../kolourpaint/document/kpDocument_Selection.cpp:146
#6  0x000000000042b5f8 in kpToolSelectionDestroyCommand::unexecute (this=0x1701ca0) at ../../kolourpaint/commands/tools/selection/kpToolSelectionDestroyCommand.cpp:166
#7  0x0000000000425978 in kpCommandHistoryBase::undoInternal (this=0xe9e9a0) at ../../kolourpaint/commands/kpCommandHistoryBase.cpp:325
#8  0x0000000000426cf9 in kpCommandHistoryBase::undo (this=0x1bbfc20) at ../../kolourpaint/commands/kpCommandHistoryBase.cpp:390
#9  0x0000000000425ee6 in kpCommandHistoryBase::qt_metacall (this=0xe9e9a0, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff0592cfa0) at ./kpCommandHistoryBase.moc:81
#10 0x00000000004282b8 in kpCommandHistory::qt_metacall (this=0x1bbfc20, _c=QMetaObject::InvokeMetaMethod, _id=-64, _a=0x0) at ./kpCommandHistory.moc:62
#11 0x00007fe1d6c21df2 in QMetaObject::activate (sender=0xe9ea50, from_signal_index=<value optimized out>, to_signal_index=6, argv=0x0) at kernel/qobject.cpp:3112
#12 0x00007fe1d6080147 in QAction::triggered (this=0x1bbfc20, _t1=false) at .moc/release-shared/moc_qaction.cpp:236
#13 0x00007fe1d60815c0 in QAction::activate (this=0xe9ea50, event=<value optimized out>) at kernel/qaction.cpp:1167
#14 0x00007fe1d63f8eda in QAbstractButtonPrivate::click (this=0x1769750) at widgets/qabstractbutton.cpp:525
#15 0x00007fe1d63f9175 in QAbstractButton::mouseReleaseEvent (this=0x171f670, e=0x7fff0592d900) at widgets/qabstractbutton.cpp:1115
#16 0x00007fe1d64c7c2a in QToolButton::mouseReleaseEvent (this=0x1bbfc20, e=0x0) at widgets/qtoolbutton.cpp:709
#17 0x00007fe1d60d637f in QWidget::event (this=0x171f670, event=0x7fff0592d900) at kernel/qwidget.cpp:7554
#18 0x00007fe1d608601d in QApplicationPrivate::notify_helper (this=0xe35cf0, receiver=0x171f670, e=0x7fff0592d900) at kernel/qapplication.cpp:4065
#19 0x00007fe1d608e7ca in QApplication::notify (this=<value optimized out>, receiver=0x171f670, e=0x7fff0592d900) at kernel/qapplication.cpp:3767
#20 0x00007fe1d7827de6 in KApplication::notify (this=0x7fff0592f6b0, receiver=0x171f670, event=0x7fff0592d900) at ../../kdeui/kernel/kapplication.cpp:302
#21 0x00007fe1d6c0cc9c in QCoreApplication::notifyInternal (this=0x7fff0592f6b0, receiver=0x171f670, event=0x7fff0592d900) at kernel/qcoreapplication.cpp:610
#22 0x00007fe1d608da78 in QCoreApplication::sendSpontaneousEvent (receiver=0x171f670, event=0x7fff0592d900, alienWidget=0x171f670, nativeWidget=0x17620f0, buttonDown=<value optimized out>, 
    lastMouseReceiver=...) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:216
#23 QApplicationPrivate::sendMouseEvent (receiver=0x171f670, event=0x7fff0592d900, alienWidget=0x171f670, nativeWidget=0x17620f0, buttonDown=<value optimized out>, lastMouseReceiver=...)
    at kernel/qapplication.cpp:2924
#24 0x00007fe1d60f6659 in QETWidget::translateMouseEvent (this=0x17620f0, event=<value optimized out>) at kernel/qapplication_x11.cpp:4411
#25 0x00007fe1d60f540f in QApplication::x11ProcessEvent (this=0x7fff0592f6b0, event=0x7fff0592f2d0) at kernel/qapplication_x11.cpp:3552
#26 0x00007fe1d611d76c in x11EventSourceDispatch (s=0xe389a0, callback=0, user_data=0x0) at kernel/qguieventdispatcher_glib.cpp:146
#27 0x00007fe1d1dca6c2 in g_main_dispatch (context=0xe37f00) at /tmp/buildd/glib2.0-2.24.0/glib/gmain.c:1960
#28 IA__g_main_context_dispatch (context=0xe37f00) at /tmp/buildd/glib2.0-2.24.0/glib/gmain.c:2513
#29 0x00007fe1d1dce538 in g_main_context_iterate (context=0xe37f00, block=<value optimized out>, dispatch=<value optimized out>, self=<value optimized out>)
    at /tmp/buildd/glib2.0-2.24.0/glib/gmain.c:2591
#30 0x00007fe1d1dce6ec in IA__g_main_context_iteration (context=0xe37f00, may_block=1) at /tmp/buildd/glib2.0-2.24.0/glib/gmain.c:2654
#31 0x00007fe1d6c3539c in QEventDispatcherGlib::processEvents (this=0xe1af70, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:407
#32 0x00007fe1d611cf1f in QGuiEventDispatcherGlib::processEvents (this=0x1bbfc20, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#33 0x00007fe1d6c0b562 in QEventLoop::processEvents (this=<value optimized out>, flags=...) at kernel/qeventloop.cpp:149
#34 0x00007fe1d6c0b934 in QEventLoop::exec (this=0x7fff0592f600, flags=...) at kernel/qeventloop.cpp:201
#35 0x00007fe1d6c0dba4 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#36 0x000000000045306d in main (argc=<value optimized out>, argv=<value optimized out>) at ../../kolourpaint/kolourpaint.cpp:125

Reported using DrKonqi