Version:            (using KDE 4.1.3)
Installed from:    Compiled From Sources

Steps to reproduce:
1. Select paint brush 
2. Settings-> Custom brush 
3. Change here Selection mode to any other
4. Crash

Application: Krita (krita), signal SIGABRT
[Thread debugging using libthread_db enabled]
[New Thread 0xb7f6f790 (LWP 3129)]
[New Thread 0xb52ffb90 (LWP 3139)]
[KCrash handler]
#6  0x00110416 in __kernel_vsyscall ()
#7  0x01cb8660 in raise () from /lib/libc.so.6
#8  0x01cba028 in abort () from /lib/libc.so.6
#9  0x00111f1a in qtMessageHandler (type=QtFatalMsg, 
    msg=0xb52fd03c "ASSERT: \"brush\" in file /home/lukas/src/koffice/krita/plugins/paintops/defaultpaintops/brush/kis_brushop.cpp, line 83")
    at /home/lukas/src/koffice/krita/main.cc:36
#10 0x00521905 in qt_message_output () from /usr/lib/libQtCore.so.4
#11 0x00521a42 in qFatal () from /usr/lib/libQtCore.so.4
#12 0x00521ae5 in qt_assert () from /usr/lib/libQtCore.so.4
#13 0x026877cd in KisBrushOp::paintAt (this=0x9afdfb8, info=@0xb52ff224)
    at /home/lukas/src/koffice/krita/plugins/paintops/defaultpaintops/brush/kis_brushop.cpp:83
#14 0x0042975e in KisPainter::paintAt (this=0x9be3ab0, pi=@0xb52ff224)
    at /home/lukas/src/koffice/krita/image/kis_painter.cc:641
#15 0x002aeac2 in FreehandPaintAtJob::run (this=0xa2b1d38)
    at /home/lukas/src/koffice/krita/ui/tool/kis_tool_freehand_p.cpp:64
#16 0x0051f960 in ?? () from /usr/lib/libQtCore.so.4
#17 0x005298ae in ?? () from /usr/lib/libQtCore.so.4
#18 0x00dce32f in start_thread () from /lib/libpthread.so.0
#19 0x01d6c20e in clone () from /lib/libc.so.6

Thread 1 (Thread 0xb7f6f790 (LWP 3129)):
#0  0x00110416 in __kernel_vsyscall ()
#1  0x01d64671 in select () from /lib/libc.so.6
#2  0x03cb9295 in ?? () from /usr/lib/libxcb.so.1
#3  0x03cbac82 in xcb_wait_for_reply () from /usr/lib/libxcb.so.1
#4  0x06247e41 in _XReply () from /usr/lib/libX11.so.6
#5  0x0623ca31 in XTranslateCoordinates () from /usr/lib/libX11.so.6
#6  0x01258d60 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#7  0x01258db1 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#8  0x01258db1 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#9  0x01258db1 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#10 0x01258db1 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#11 0x01258db1 in QWidget::mapFromGlobal () from /usr/lib/libQtGui.so.4
#12 0x00a130d5 in KoDocument::hitTest (this=0x92fc930, widget=0x93593a0, 
    globalPos=@0xbf9a7534)
    at /home/lukas/src/koffice/libs/main/KoDocument.cpp:724
#13 0x00212741 in KisDoc2::hitTest (this=0x92fc930, w=0x93593a0, 
    pt=@0xbf9a7534) at /home/lukas/src/koffice/krita/ui/kis_doc2.h:82
#14 0x00cf27b4 in KParts::PartManager::findPartFromWidget ()
   from /usr/lib/libkparts.so.4
#15 0x00cf387a in KParts::PartManager::eventFilter ()
   from /usr/lib/libkparts.so.4
#16 0x00a3b5aa in KoPartManager::eventFilter (this=0x93003b8, obj=0x9a79070, 
    ev=0xbf9a7754) at /home/lukas/src/koffice/libs/main/KoMainWindow.cpp:94
#17 0x00619574 in QCoreApplicationPrivate::sendThroughApplicationEventFilters
    () from /usr/lib/libQtCore.so.4
#18 0x011cef03 in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#19 0x011d77e1 in QApplication::notify () from /usr/lib/libQtGui.so.4
#20 0x0715c95d in KApplication::notify () from /usr/lib/libkdeui.so.5
#21 0x0061a2e1 in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#22 0x011d6a6e in QApplicationPrivate::sendMouseEvent ()
   from /usr/lib/libQtGui.so.4
#23 0x01240f26 in ?? () from /usr/lib/libQtGui.so.4
#24 0x012402ad in QApplication::x11ProcessEvent () from /usr/lib/libQtGui.so.4
#25 0x01268a3c in ?? () from /usr/lib/libQtGui.so.4
#26 0x01e2de38 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#27 0x01e314e3 in ?? () from /lib/libglib-2.0.so.0
#28 0x01e316a1 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#29 0x00644a28 in QEventDispatcherGlib::processEvents ()
   from /usr/lib/libQtCore.so.4
#30 0x01268105 in ?? () from /usr/lib/libQtGui.so.4
#31 0x006189ca in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#32 0x00618b8a in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#33 0x0061b235 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#34 0x011cee07 in QApplication::exec () from /usr/lib/libQtGui.so.4
#35 0x001135a0 in kdemain (argc=1, argv=0xbf9a8324)
    at /home/lukas/src/koffice/krita/main.cc:56
#36 0x080489c6 in main (argc=256, argv=0x0)
    at /home/lukas/src/build/koffice/krita/krita_dummy.cpp:3