Version:            (using KDE 4.2.1)
Installed from:    Ubuntu Packages

I was just deleting a simple message as I did thousand of times with KMail 4.2.1 and this time it crashed leaving this backtrace

Application: KMail (kmail), signal SIGSEGV
[Current thread is 0 (LWP 23022)]

Thread 2 (Thread 0xb0cd7b90 (LWP 23319)):
#0  0xb8014424 in __kernel_vsyscall ()
#1  0xb5db9df1 in select () from /lib/tls/i686/cmov/libc.so.6
#2  0xb6088150 in ?? () from /usr/lib/libQtCore.so.4
#3  0xb5fb86ae in ?? () from /usr/lib/libQtCore.so.4
#4  0xb520350f in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#5  0xb5dc1a0e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb3f8c6c0 (LWP 23022)):
[KCrash Handler]
#6  KMail::FolderJob::msgList (this=0xcf11400) at /usr/include/qt4/QtCore/qatomic_i386.h:116
#7  0xb74dbdab in KMAcctImap::ignoreJobsForMessage (this=0x9ebf410, msg=0xb21b838) at /build/buildd/kdepim-4.2.1/kmail/kmacctimap.cpp:215
#8  0xb74f4885 in KMFolderImap::ignoreJobsForMessage (this=0xa07b858, msg=0xb21b838) at /build/buildd/kdepim-4.2.1/kmail/kmfolderimap.cpp:1562
#9  0xb76152fe in KMMoveCommand::execute (this=0xa517730) at /build/buildd/kdepim-4.2.1/kmail/kmcommands.cpp:2086
#10 0xb75f8b92 in KMCommand::slotPostTransfer (this=0xa517730, result=KMCommand::OK) at /build/buildd/kdepim-4.2.1/kmail/kmcommands.cpp:276
#11 0xb76044f4 in KMCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=5, _a=0xbf913c2c) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:86
#12 0xb76171da in KMMoveCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=9, _a=0xbf913c2c) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:1662
#13 0xb76172a2 in KMDeleteMsgCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=9, _a=0xbf913c2c) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:1712
#14 0xb60bda60 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#15 0xb60be7e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#16 0xb75f5243 in KMCommand::messagesTransfered (this=0xa517730, _t1=KMCommand::OK) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:100
#17 0xb7613b2c in KMCommand::transferSelectedMsgs (this=0xa517730) at /build/buildd/kdepim-4.2.1/kmail/kmcommands.cpp:370
#18 0xb7613d7f in KMCommand::slotStart (this=0xa517730) at /build/buildd/kdepim-4.2.1/kmail/kmcommands.cpp:268
#19 0xb7604503 in KMCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=4, _a=0xbf913e28) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:85
#20 0xb76171da in KMMoveCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0xbf913e28) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:1662
#21 0xb76172a2 in KMDeleteMsgCommand::qt_metacall (this=0xa517730, _c=QMetaObject::InvokeMetaMethod, _id=8, _a=0xbf913e28) at /build/buildd/kdepim-4.2.1/obj-i486-linux-gnu/kmail/kmcommands.moc:1712
#22 0xb60bda60 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#23 0xb60be7e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#24 0xb60c3db7 in ?? () from /usr/lib/libQtCore.so.4
#25 0xb60c3edc in ?? () from /usr/lib/libQtCore.so.4
#26 0xb60b853f in QObject::event () from /usr/lib/libQtCore.so.4
#27 0xb63388ec in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#28 0xb634072e in QApplication::notify () from /usr/lib/libQtGui.so.4
#29 0xb7e2e10d in KApplication::notify (this=0xbf9145d8, receiver=0xaa45d40, event=0xbf9142bc) at /build/buildd/kde4libs-4.2.1a/kdeui/kernel/kapplication.cpp:307
#30 0xb60a8e61 in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#31 0xb60d6d81 in ?? () from /usr/lib/libQtCore.so.4
#32 0xb60d3520 in ?? () from /usr/lib/libQtCore.so.4
#33 0xb46ec718 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#34 0xb46efdc3 in ?? () from /usr/lib/libglib-2.0.so.0
#35 0xb46eff81 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#36 0xb60d3478 in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#37 0xb63d2ea5 in ?? () from /usr/lib/libQtGui.so.4
#38 0xb60a752a in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#39 0xb60a76ea in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#40 0xb60a9da5 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#41 0xb6338767 in QApplication::exec () from /usr/lib/libQtGui.so.4
#42 0x0804a7a0 in main (argc=) at /build/buildd/kdepim-4.2.1/kmail/main.cpp:146