Application: plasma-desktop (0.3)
KDE Platform Version: 4.4.1 (KDE 4.4.1)
Qt Version: 4.6.2
Operating System: Linux 2.6.32-ARCH x86_64
Distribution (Platform): Archlinux Packages

-- Information about the crash:
I was just working in dolphin and gvim on my laptop.
My battery reached a low/critical level and i got the notification.
Not one second later plasma crashes (but recovers).

 -- Backtrace:
Application: Plasma Workspace (kdeinit4), signal: Bus error
[KCrash Handler]
#5  0x00007f4db7e956c0 in KPixmapCache::Private::mmapFile(QString const&, KPixmapCache::Private::MmapInfo*, int) () from /usr/lib/libkdeui.so.5
#6  0x00007f4db7e96f64 in KPixmapCache::Private::mmapFiles() () from /usr/lib/libkdeui.so.5
#7  0x00007f4db7e96d83 in KPixmapCache::Private::init() () from /usr/lib/libkdeui.so.5
#8  0x00007f4db7e987ed in KPixmapCache::discard() () from /usr/lib/libkdeui.so.5
#9  0x00007f4db7e98ed8 in KPixmapCache::deleteCache(QString const&) () from /usr/lib/libkdeui.so.5
#10 0x00007f4daf135fad in Plasma::ThemePrivate::discardCache() () from /usr/lib/libplasma.so.3
#11 0x00007f4daf13640d in Plasma::ThemePrivate::compositingChanged() () from /usr/lib/libplasma.so.3
#12 0x00007f4daf13bf62 in Plasma::Theme::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libplasma.so.3
#13 0x00007f4db78f74df in QMetaObject::activate(QObject*, QMetaObject const*, int, void**) () from /usr/lib/libQtCore.so.4
#14 0x00007f4db7e8f4cd in KSelectionWatcher::Private::x11Event(_XEvent*) () from /usr/lib/libkdeui.so.5
#15 0x00007f4db7e16206 in KApplication::x11EventFilter(_XEvent*) () from /usr/lib/libkdeui.so.5
#16 0x00007f4daa0bb3d4 in PlasmaApp::x11EventFilter(_XEvent*) () from /usr/lib/libkdeinit4_plasma-desktop.so
#17 0x00007f4db6b01741 in ?? () from /usr/lib/libQtGui.so.4
#18 0x00007f4db6b10221 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/libQtGui.so.4
#19 0x00007f4db6b3b172 in ?? () from /usr/lib/libQtGui.so.4
#20 0x00007f4db2d5326e in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#21 0x00007f4db2d56c28 in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#22 0x00007f4db2d56d50 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#23 0x00007f4db790dc13 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#24 0x00007f4db6b3ad6e in ?? () from /usr/lib/libQtGui.so.4
#25 0x00007f4db78e30c2 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#26 0x00007f4db78e349c in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#27 0x00007f4db78e71db in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#28 0x00007f4daa0a9d22 in kdemain () from /usr/lib/libkdeinit4_plasma-desktop.so
#29 0x0000000000406b7e in _start ()

Reported using DrKonqi