Version:            (using KDE 4.2.4)
Installed from:    Slackware Packages

Steps to reproduce:

Unknown - I'm now getting the following traceback (after having re-built Qt and kdepim with debugging enabled to try and track down a different bug elsewhere) every time I log into X and start KDE:

Application: Printer Applet (printer-applet), signal SIGABRT
0x00007f3edac62850 in __nanosleep_nocancel () from /lib64/libc.so.6

Thread 1 (Thread 0x7f3edbd7c6f0 (LWP 2300)):
[KCrash Handler]
#5  0x00007f3edabedea5 in raise () from /lib64/libc.so.6
#6  0x00007f3edabefab3 in abort () from /lib64/libc.so.6
#7  0x00007f3ed94e2ef5 in qt_message_output (msgType=QtFatalMsg, buf=<value optimized out>) at global/qglobal.cpp:2017
#8  0x00007f3ed94e303b in qFatal (msg=<value optimized out>) at global/qglobal.cpp:2216
#9  0x00007f3ed32cbc8f in QDBusConnection::registerObject (this=0x7fff0131fe80, path=@0x260deb0, object=0x260efa0, options={i = 20053856}) at qdbusconnection.cpp:706
#10 0x00007f3ed1b26e0f in ?? () from /usr/lib64/libkdeui.so.5
#11 0x00007f3ed1b26f8d in KMainWindow::event () from /usr/lib64/libkdeui.so.5
#12 0x00007f3ed1b63948 in KXmlGuiWindow::event () from /usr/lib64/libkdeui.so.5
#13 0x00007f3ed21264f3 in sipKXmlGuiWindow::event () from /usr/lib64/python2.6/site-packages/PyKDE4/kdeui.so
#14 0x00007f3ed6664d6d in QApplicationPrivate::notify_helper (this=0x24eb2b0, receiver=0x260efa0, e=0x7fff01320560) at kernel/qapplication.cpp:4057
#15 0x00007f3ed666b5ae in QApplication::notify (this=0x24ea0d0, receiver=0x260efa0, e=0x7fff01320560) at kernel/qapplication.cpp:4022
#16 0x00007f3ed1a5f2fb in KApplication::notify () from /usr/lib64/libkdeui.so.5
#17 0x00007f3ed22d5f76 in sipKApplication::notify () from /usr/lib64/python2.6/site-packages/PyKDE4/kdeui.so
#18 0x00007f3ed95e058c in QCoreApplication::notifyInternal (this=0x24ea0d0, receiver=0x260efa0, event=0x7fff01320560) at kernel/qcoreapplication.cpp:610
#19 0x00007f3ed66aff5f in QWidget::ensurePolished (this=0x260efa0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#20 0x00007f3ed66bb493 in QWidget::event (this=0x260efa0, event=0x260ec70) at kernel/qwidget.cpp:7592
#21 0x00007f3ed6aa8dfb in QMainWindow::event (this=0x260efa0, event=0x260ec70) at widgets/qmainwindow.cpp:1402
#22 0x00007f3ed1b63948 in KXmlGuiWindow::event () from /usr/lib64/libkdeui.so.5
#23 0x00007f3ed21264f3 in sipKXmlGuiWindow::event () from /usr/lib64/python2.6/site-packages/PyKDE4/kdeui.so
#24 0x00007f3ed6664d6d in QApplicationPrivate::notify_helper (this=0x24eb2b0, receiver=0x260efa0, e=0x260ec70) at kernel/qapplication.cpp:4057
#25 0x00007f3ed666b5ae in QApplication::notify (this=0x24ea0d0, receiver=0x260efa0, e=0x260ec70) at kernel/qapplication.cpp:4022
#26 0x00007f3ed1a5f2fb in KApplication::notify () from /usr/lib64/libkdeui.so.5
#27 0x00007f3ed22d5f76 in sipKApplication::notify () from /usr/lib64/python2.6/site-packages/PyKDE4/kdeui.so
#28 0x00007f3ed95e058c in QCoreApplication::notifyInternal (this=0x24ea0d0, receiver=0x260efa0, event=0x260ec70) at kernel/qcoreapplication.cpp:610
#29 0x00007f3ed95e155c in QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x224cfb0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#30 0x00007f3ed960d093 in postEventSourceDispatch (s=<value optimized out>) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#31 0x00007f3ed8dcc28b in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
#32 0x00007f3ed8dcfa4d in ?? () from /usr/lib64/libglib-2.0.so.0
#33 0x00007f3ed8dcfc0b in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#34 0x00007f3ed960cdbf in QEventDispatcherGlib::processEvents (this=0x24ea310, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:324
#35 0x00007f3ed670402f in QGuiEventDispatcherGlib::processEvents (this=0x8fc, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#36 0x00007f3ed95df082 in QEventLoop::processEvents (this=<value optimized out>, flags={i = 20058032}) at kernel/qeventloop.cpp:149
#37 0x00007f3ed95df44d in QEventLoop::exec (this=0x7fff01320ff0, flags={i = 20058112}) at kernel/qeventloop.cpp:200
#38 0x00007f3ed95e1874 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#39 0x00007f3ed76ace4c in ?? () from /usr/lib64/python2.6/site-packages/PyQt4/QtGui.so
#40 0x00007f3edb8bdffe in PyEval_EvalFrameEx () from /usr/lib64/libpython2.6.so.1.0
#41 0x00007f3edb8bfbe9 in PyEval_EvalCodeEx () from /usr/lib64/libpython2.6.so.1.0
#42 0x00007f3edb8bfd02 in PyEval_EvalCode () from /usr/lib64/libpython2.6.so.1.0
#43 0x00007f3edb8e03ca in PyRun_FileExFlags () from /usr/lib64/libpython2.6.so.1.0
#44 0x00007f3edb8e06bd in PyRun_SimpleFileExFlags () from /usr/lib64/libpython2.6.so.1.0
#45 0x00007f3edb8edd03 in Py_Main () from /usr/lib64/libpython2.6.so.1.0
#46 0x00007f3edabd9526 in __libc_start_main () from /lib64/libc.so.6
#47 0x0000000000400639 in _start ()