Application: kmail (1.13.6)
KDE Platform Version: 4.6.5 (4.6.5)
Qt Version: 4.7.2
Operating System: Linux 2.6.38-10-generic i686
Distribution: Ubuntu 11.04

-- Information about the crash:
- What I was doing when the application crashed:
I was sending an email, then I opened the message -double-click- (in outbox) that I was sending to review it. Then I put the cursor in A field, when I realise that was correct, I closed the window. And Kmail main window disappeared too. I tried to relanch Kmail, but I didn't realise that the previous instance was running (without window), previous instance crashed and the new instance says that would be dangerous to run two instances of Kmail.
- Custom settings of the application:
A POP3 account, and two SMTP accounts configured. Locale: Catalan.

-- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[Current thread is 1 (Thread 0xb7834780 (LWP 1970))]

Thread 3 (Thread 0xb4920b70 (LWP 1989)):
#0  0x0094f416 in __kernel_vsyscall ()
#1  0x00849f76 in poll () from /lib/i386-linux-gnu/libc.so.6
#2  0x0224184b in g_poll () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0x022311af in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0x0223192b in g_main_loop_run () from /lib/i386-linux-gnu/libglib-2.0.so.0
#5  0x03711304 in ?? () from /usr/lib/i386-linux-gnu/libgio-2.0.so.0
#6  0x0225a2df in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#7  0x00b13e99 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#8  0x0085873e in clone () from /lib/i386-linux-gnu/libc.so.6

Thread 2 (Thread 0xb52feb70 (LWP 2003)):
#0  0x00b1636b in pthread_mutex_lock () from /lib/i386-linux-gnu/libpthread.so.0
#1  0x00866616 in pthread_mutex_lock () from /lib/i386-linux-gnu/libc.so.6
#2  0x0223033d in g_main_context_query () from /lib/i386-linux-gnu/libglib-2.0.so.0
#3  0x02230e8c in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#4  0x02231524 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#5  0x00678577 in QEventDispatcherGlib::processEvents (this=0xa3f1720, flags=...) at kernel/qeventdispatcher_glib.cpp:424
#6  0x0064a289 in QEventLoop::processEvents (this=0xb52fe220, flags=...) at kernel/qeventloop.cpp:149
#7  0x0064a522 in QEventLoop::exec (this=0xb52fe220, flags=...) at kernel/qeventloop.cpp:201
#8  0x005542a0 in QThread::exec (this=0xa4244c8) at thread/qthread.cpp:492
#9  0x0062bfdb in QInotifyFileSystemWatcherEngine::run (this=0xa4244c8) at io/qfilesystemwatcher_inotify.cpp:248
#10 0x00556da2 in QThreadPrivate::start (arg=0xa4244c8) at thread/qthread_unix.cpp:320
#11 0x00b13e99 in start_thread () from /lib/i386-linux-gnu/libpthread.so.0
#12 0x0085873e in clone () from /lib/i386-linux-gnu/libc.so.6

Thread 1 (Thread 0xb7834780 (LWP 1970)):
[KCrash Handler]
#7  0x00f6469a in KMMessage::transferInProgress (this=0xa726a40) at ../../kmail/kmmessage.cpp:271
#8  0x01053168 in FolderStorage::canAddMsgNow (this=0x9ddda90, aMsg=0xa726a40, aIndex_ret=0x0) at ../../kmail/folderstorage.cpp:311
#9  0x01123c48 in KMFolderMaildir::addMsg (this=0x9ddda90, aMsg=0xa726a40, index_return=0x0) at ../../kmail/kmfoldermaildir.cpp:322
#10 0x01026b25 in KMFolder::addMsg (this=0x9d81898, msg=0xa726a40, index_return=0x0) at ../../kmail/kmfolder.cpp:448
#11 0x0100f081 in KMComposeWin::~KMComposeWin (this=0xa48a560, __in_chrg=<value optimized out>, __vtt_parm=<value optimized out>) at ../../kmail/kmcomposewin.cpp:407
#12 0x0100f952 in KMComposeWin::~KMComposeWin (this=0xa48a560, __in_chrg=<value optimized out>, __vtt_parm=<value optimized out>) at ../../kmail/kmcomposewin.cpp:432
#13 0x0065dbc5 in qDeleteInEventHandler (o=0xa48a560) at kernel/qobject.cpp:3995
#14 0x006603e8 in QObject::event (this=0xa48a560, e=0xa5b4310) at kernel/qobject.cpp:1209
#15 0x04ed7b62 in QWidget::event (this=0xa48a560, event=0xa5b4310) at kernel/qwidget.cpp:8718
#16 0x052e9527 in QMainWindow::event (this=0xa48a560, event=0xa5b4310) at widgets/qmainwindow.cpp:1480
#17 0x00deb1ec in KMainWindow::event (this=0xa48a560, ev=0xa5b4310) at ../../kdeui/widgets/kmainwindow.cpp:1100
#18 0x00e2ba8f in KXmlGuiWindow::event (this=0xa48a560, ev=0xa5b4310) at ../../kdeui/xmlgui/kxmlguiwindow.cpp:126
#19 0x04e7fd24 in QApplicationPrivate::notify_helper (this=0x9beec58, receiver=0xa48a560, e=0xa5b4310) at kernel/qapplication.cpp:4462
#20 0x04e8497b in QApplication::notify (this=0xbfaaae1c, receiver=0xa48a560, e=0xa5b4310) at kernel/qapplication.cpp:4427
#21 0x00d1032a in KApplication::notify (this=0xbfaaae1c, receiver=0xa48a560, event=0xa5b4310) at ../../kdeui/kernel/kapplication.cpp:311
#22 0x0064b0bb in QCoreApplication::notifyInternal (this=0xbfaaae1c, receiver=0xa48a560, event=0xa5b4310) at kernel/qcoreapplication.cpp:731
#23 0x0064ec79 in sendEvent (receiver=0x0, event_type=0, data=0x9b5ff28) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:215
#24 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x9b5ff28) at kernel/qcoreapplication.cpp:1372
#25 0x0064ee0d in QCoreApplication::sendPostedEvents (receiver=0x0, event_type=0) at kernel/qcoreapplication.cpp:1265
#26 0x006783c4 in sendPostedEvents (s=0x9bdcf00) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:220
#27 postEventSourceDispatch (s=0x9bdcf00) at kernel/qeventdispatcher_glib.cpp:277
#28 0x02230aa8 in g_main_context_dispatch () from /lib/i386-linux-gnu/libglib-2.0.so.0
#29 0x02231270 in ?? () from /lib/i386-linux-gnu/libglib-2.0.so.0
#30 0x02231524 in g_main_context_iteration () from /lib/i386-linux-gnu/libglib-2.0.so.0
#31 0x0067853c in QEventDispatcherGlib::processEvents (this=0x9b5fa80, flags=...) at kernel/qeventdispatcher_glib.cpp:422
#32 0x04f361e5 in QGuiEventDispatcherGlib::processEvents (this=0x9b5fa80, flags=...) at kernel/qguieventdispatcher_glib.cpp:204
#33 0x0064a289 in QEventLoop::processEvents (this=0xbfaaace4, flags=...) at kernel/qeventloop.cpp:149
#34 0x0064a522 in QEventLoop::exec (this=0xbfaaace4, flags=...) at kernel/qeventloop.cpp:201
#35 0x0064eecc in QCoreApplication::exec () at kernel/qcoreapplication.cpp:1008
#36 0x04e7d8e7 in QApplication::exec () at kernel/qapplication.cpp:3736
#37 0x0804a733 in main (argc=960842031, argv=0x6c69662c) at ../../kmail/main.cpp:158

Reported using DrKonqi