Application that crashed: kmail
Version of the application: 1.12.90
KDE Version: 4.3.61 (KDE 4.3.61 (KDE 4.4 >= 20090717)) "release 3"
Qt Version: 4.5.2
Operating System: Linux 2.6.30.1-9-default-jta x86_64

What I was doing when the application crashed:
This may be a kdelibs (kconfig) crash.
kmail was running fine in background, with the machine very busy, and then crash.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#5  QByteArray (this=0x7ffd89da1f10, data=0x46a118f "/etc/kde4/\ndir_locale=/usr/share/locale-bundle\ndir_html=/usr/share/doc-bundle\n", size=10) at tools/qbytearray.cpp:1266
#6  0x00007f5bf5ab35af in KConfigIniBackend::parseConfig (this=<value optimized out>, currentLocale=@0x7fff89da21e0, entryMap=@0x4609aa0, options={i = -1982193328}, merging=false)
    at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/config/bufferfragment_p.h:167
#7  0x00007f5bf5ab44a4 in KConfigIniBackend::parseConfig (this=0x31d9760, currentLocale=@0x2a, entryMap=@0x37, options=<value optimized out>)
    at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/config/kconfigini.cpp:66
#8  0x00007f5bf5a9dce8 in KConfigPrivate::parseGlobalFiles (this=<value optimized out>) at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/config/kconfig.cpp:479
#9  0x00007f5bf5a9f2cd in KConfig::reparseConfiguration (this=<value optimized out>) at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/config/kconfig.cpp:446
#10 0x00007f5bf5aa1193 in KConfig (this=0x4d87750, file=@0x7fff89da22d0, mode=<value optimized out>, resourceType=0x7f5bf5c21317 "config")
    at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/config/kconfig.cpp:161
#11 0x00007f5bf5b6c037 in Sonnet::defaultLanguageName () at /usr/src/debug/kdelibs-4.3.61svn998540/kdecore/sonnet/globals.cpp:89
#12 0x00007f5bf48c07c7 in KPIMIdentities::Identity::isNull (this=0x28dcde0) at /usr/src/debug/kdepimlibs-4.3.61svn998540/kpimidentities/identity.cpp:86
#13 0x00007f5bf51ec75a in KMFolder::slotIdentitiesChanged (this=0x2a458a0) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/kmfolder.cpp:960
#14 0x00007f5bf51f1ec2 in KMFolder::readConfig (this=0x2a458a0, configGroup=@0x7fff89da2730) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/kmfolder.cpp:210
#15 0x00007f5bf521e414 in FolderStorage::readConfig (this=0x2a587b0) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderstorage.cpp:963
#16 0x00007f5bf52e2c39 in KMFolderCachedImap::readConfig (this=0x2a587b0) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/kmfoldercachedimap.cpp:314
#17 0x00007f5bf521a660 in FolderStorage::countUnread (this=0x31d9760) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderstorage.cpp:866
#18 0x00007f5bf51a0418 in KMail::FolderViewItem::updateCounts (this=0x3834260) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderview.cpp:2843
#19 0x00007f5bf51a0858 in KMail::FolderView::updateCountsForChildren (this=0x3600390, it=0x3833fb0, tStart=@0x7fff89da2d30) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderview.cpp:865
#20 0x00007f5bf51a07c3 in KMail::FolderView::updateCountsForChildren (this=0x3600390, it=0x3833f00, tStart=@0x7fff89da2d30) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderview.cpp:837
#21 0x00007f5bf51a07c3 in KMail::FolderView::updateCountsForChildren (this=0x3600390, it=0x36183f0, tStart=@0x7fff89da2d30) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderview.cpp:837
#22 0x00007f5bf51a08cf in KMail::FolderView::slotUpdateCounts (this=0x3600390) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/folderview.cpp:898
#23 0x00007f5bf51a1035 in KMail::FolderView::qt_metacall (this=0x3600390, _c=QMetaObject::InvokeMetaMethod, _id=<value optimized out>, _a=0x7fff89da2e30)
    at /usr/src/debug/kdepim-4.3.61svn998540/build/kmail/folderview.moc:211
#24 0x00007f5bf51a4166 in KMail::MainFolderView::qt_metacall (this=0x31d9760, _c=42, _id=55, _a=0xd) at /usr/src/debug/kdepim-4.3.61svn998540/build/kmail/mainfolderview.moc:64
#25 0x00007f5bf2bbd6e2 in QMetaObject::activate (sender=0x36386f0, from_signal_index=<value optimized out>, to_signal_index=4, argv=0xd) at kernel/qobject.cpp:3113
#26 0x00007f5bf2bb8533 in QObject::event (this=0x36386f0, e=0x2a) at kernel/qobject.cpp:1075
#27 0x00007f5bf18c6b0d in QApplicationPrivate::notify_helper (this=0x25e2a20, receiver=0x36386f0, e=0x7fff89da3520) at kernel/qapplication.cpp:4056
#28 0x00007f5bf18ced9a in QApplication::notify (this=0x7fff89da3a30, receiver=0x36386f0, e=0x7fff89da3520) at kernel/qapplication.cpp:4021
#29 0x00007f5bf6095bcb in KApplication::notify (this=0x7fff89da3a30, receiver=0x36386f0, event=0x7fff89da3520) at /usr/src/debug/kdelibs-4.3.61svn998540/kdeui/kernel/kapplication.cpp:302
#30 0x00007f5bf2ba894c in QCoreApplication::notifyInternal (this=0x7fff89da3a30, receiver=0x36386f0, event=0x7fff89da3520) at kernel/qcoreapplication.cpp:610
#31 0x00007f5bf2bd5b60 in QTimerInfoList::activateTimers (this=0x25e5c30) at kernel/qcoreapplication.h:213
#32 0x00007f5bf2bd1ddd in timerSourceDispatch (source=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:165
#33 0x00007f5be812b0fb in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
#34 0x00007f5be812e8cd in ?? () from /usr/lib64/libglib-2.0.so.0
#35 0x00007f5be812ea8b in g_main_context_iteration () from /usr/lib64/libglib-2.0.so.0
#36 0x00007f5bf2bd1d3f in QEventDispatcherGlib::processEvents (this=0x25a75f0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:327
#37 0x00007f5bf195dfef in QGuiEventDispatcherGlib::processEvents (this=0x31d9760, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:202
#38 0x00007f5bf2ba71d2 in QEventLoop::processEvents (this=<value optimized out>, flags={i = -1982187456}) at kernel/qeventloop.cpp:149
#39 0x00007f5bf2ba75a4 in QEventLoop::exec (this=0x7fff89da3880, flags={i = -1982187376}) at kernel/qeventloop.cpp:201
#40 0x00007f5bf2ba9894 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#41 0x00000000004030fb in main (argc=<value optimized out>, argv=<value optimized out>) at /usr/src/debug/kdepim-4.3.61svn998540/kmail/main.cpp:146

Reported using DrKonqi