Application: kontact (4.4.3)
KDE Platform Version: 4.4.3 (KDE 4.4.3)
Qt Version: 4.6.2
Operating System: Linux 2.6.32-5-686 i686
Distribution: Debian GNU/Linux unstable (sid)

-- Information about the crash:
I created a new email and tried using the Google Mail (corporate version, not GMail, but maybe its the same) address book to complete an address.  The mouse cursor just spun without getting the address so I manually typed it in.  Composed my email, attached an image, hit [Send], and Kontact crashed.  I don't know if it was the Address Book part or if the image had anything to do with it, or if I hit [Send] before the address book part gave up.

Thanks for KDE and Kontact!

The crash can be reproduced some of the time.

 -- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
[KCrash Handler]
#6  0x00000000 in ?? ()
#7  0x4a395925 in KPIM::AddresseeLineEdit::loadContacts (this=<value optimized out>) at ../../libkdepim/addresseelineedit.cpp:580
#8  0xb29783b2 in KMLineEdit::loadContacts (this=<value optimized out>) at ../../kmail/kmlineeditspell.cpp:195
#9  0x4a3983bb in KPIM::AddresseeLineEdit::doCompletion (this=<value optimized out>, ctrlT=<value optimized out>) at ../../libkdepim/addresseelineedit.cpp:422
#10 0x4a39bd95 in KPIM::AddresseeLineEdit::slotCompletion (this=<value optimized out>) at ../../libkdepim/addresseelineedit.cpp:995
#11 0x4a39d9db in KPIM::AddresseeLineEdit::qt_metacall (this=<value optimized out>, _c=<value optimized out>, _id=<value optimized out>, _a=<value optimized out>) at ./addresseelineedit.moc:97
#12 0xb297832a in KMLineEdit::qt_metacall (this=<value optimized out>, _c=<value optimized out>, _id=<value optimized out>, _a=<value optimized out>) at ./kmlineeditspell.moc:74
#13 0xb29edcfa in RecipientLineEdit::qt_metacall (this=<value optimized out>, _c=<value optimized out>, _id=<value optimized out>, _a=<value optimized out>) at ./recipientseditor.moc:135
#14 0x4a0f0e4a in QMetaObject::metacall (object=<value optimized out>, cl=<value optimized out>, idx=<value optimized out>, argv=<value optimized out>) at kernel/qmetaobject.cpp:237
#15 0x4a0ff415 in QMetaObject::activate (sender=<value optimized out>, m=<value optimized out>, local_signal_index=<value optimized out>, argv=<value optimized out>) at kernel/qobject.cpp:3293
#16 0x4b648b93 in KLineEdit::completion (this=) at ./klineedit.moc:233
#17 0x4b648d47 in KLineEdit::doCompletion (this=<value optimized out>, txt=) at ../../kdeui/widgets/klineedit.cpp:1769
#18 0x4b64d4f5 in KLineEdit::keyPressEvent (this=<value optimized out>, e=<value optimized out>) at ../../kdeui/widgets/klineedit.cpp:926
#19 0x4a39bfe6 in KPIM::AddresseeLineEdit::keyPressEvent (this=<value optimized out>, e=<value optimized out>) at ../../libkdepim/addresseelineedit.cpp:233
#20 0xb2977dfe in KMLineEdit::keyPressEvent (this=<value optimized out>, e=<value optimized out>) at ../../kmail/kmlineeditspell.cpp:77
#21 0xb29ef8fc in RecipientLineEdit::keyPressEvent (this=<value optimized out>, ev=<value optimized out>) at ../../kmail/recipientseditor.cpp:144
#22 0xb6e7db83 in QWidget::event (this=<value optimized out>, event=<value optimized out>) at kernel/qwidget.cpp:8033
#23 0xb7286fdb in QLineEdit::event (this=<value optimized out>, e=<value optimized out>) at widgets/qlineedit.cpp:1474
#24 0x4b64e99c in KLineEdit::event (this=<value optimized out>, ev=<value optimized out>) at ../../kdeui/widgets/klineedit.cpp:1329
#25 0xb6e1fbec in QApplicationPrivate::notify_helper (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:4300
#26 0xb6e28271 in QApplication::notify (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:3763
#27 0x4b5637da in KApplication::notify (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>) at ../../kdeui/kernel/kapplication.cpp:302
#28 0x4a0ebc4b in QCoreApplication::notifyInternal (this=<value optimized out>, receiver=<value optimized out>, event=<value optimized out>) at kernel/qcoreapplication.cpp:704
#29 0xb6e209ce in QCoreApplication::sendSpontaneousEvent (receiver=) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#30 qt_sendSpontaneousEvent (receiver=) at kernel/qapplication.cpp:5279
#31 0xb6ed9090 in QKeyMapper::sendKeyEvent (keyWidget=<value optimized out>, grab=) at kernel/qkeymapper_x11.cpp:1861
#32 0xb6edb570 in QKeyMapperPrivate::translateKeyEvent (this=<value optimized out>, keyWidget=<value optimized out>, event=<value optimized out>, grab=<value optimized out>)
    at kernel/qkeymapper_x11.cpp:1831
#33 0xb6eaf827 in QApplication::x11ProcessEvent (this=<value optimized out>, event=<value optimized out>) at kernel/qapplication_x11.cpp:3394
#34 0xb6ede6f2 in x11EventSourceDispatch (s=<value optimized out>, callback=<value optimized out>, user_data=) at kernel/qguieventdispatcher_glib.cpp:146
#35 0x49b602f5 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#36 0x49b63fd8 in ?? () from /lib/libglib-2.0.so.0
#37 0x49b641b8 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#38 0x4a117655 in QEventDispatcherGlib::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:412
#39 0xb6ede255 in QGuiEventDispatcherGlib::processEvents (this=) at kernel/qguieventdispatcher_glib.cpp:204
#40 0x4a0ea269 in QEventLoop::processEvents (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:149
#41 0x4a0ea6ba in QEventLoop::exec (this=<value optimized out>, flags=<value optimized out>) at kernel/qeventloop.cpp:201
#42 0x4a0ee84f in QCoreApplication::exec () at kernel/qcoreapplication.cpp:981
#43 0xb6e1fc87 in QApplication::exec () at kernel/qapplication.cpp:3579
#44 0x0804b472 in main (argc=3, argv=0xbfd7de14) at ../../../kontact/src/main.cpp:224

Reported using DrKonqi