Application that crashed: kontact
Version of the application: 4.3.2
KDE Version: 4.3.2 (KDE 4.3.2)
Qt Version: 4.5.2
Operating System: Linux 2.6.31-15-generic x86_64
Distribution: Ubuntu 9.10

What I was doing when the application crashed:
Kontact crashes while trying to sync with imap folder
It doesn't happen always, but quite frequently ~5% of the times
The account is a gmail account

 -- Backtrace:
Application: Kontact (kontact), signal: Segmentation fault
[KCrash Handler]
#5  0x00007fb63ec81720 in QByteArray::operator=(QByteArray const&) () from /usr/lib/libQtCore.so.4
#6  0x00007fb6291d9b5a in ?? () from /usr/lib/libkmailprivate.so.4
#7  0x00007fb6290cad29 in ?? () from /usr/lib/libkmailprivate.so.4
#8  0x00007fb62936c8da in KMHandleAttachmentCommand::slotStart() () from /usr/lib/libkmailprivate.so.4
#9  0x00007fb62935b5d6 in KMHandleAttachmentCommand::qt_metacall(QMetaObject::Call, int, void**) () from /usr/lib/libkmailprivate.so.4
#10 0x00007fb63ed7addc in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/libQtCore.so.4
#11 0x00007fb63ed7fe1f in ?? () from /usr/lib/libQtCore.so.4
#12 0x00007fb63ed74d83 in QObject::event(QEvent*) () from /usr/lib/libQtCore.so.4
#13 0x00007fb63f685efc in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#14 0x00007fb63f68d1ce in QApplication::notify(QObject*, QEvent*) () from /usr/lib/libQtGui.so.4
#15 0x00007fb6402bcab6 in KApplication::notify(QObject*, QEvent*) () from /usr/lib/libkdeui.so.5
#16 0x00007fb63ed65c2c in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/libQtCore.so.4
#17 0x00007fb63ed90862 in ?? () from /usr/lib/libQtCore.so.4
#18 0x00007fb63ed8e25d in ?? () from /usr/lib/libQtCore.so.4
#19 0x00007fb6385dfbbe in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#20 0x00007fb6385e3588 in ?? () from /lib/libglib-2.0.so.0
#21 0x00007fb6385e36b0 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#22 0x00007fb63ed8e1a6 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#23 0x00007fb63f71a4be in ?? () from /usr/lib/libQtGui.so.4
#24 0x00007fb63ed64532 in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#25 0x00007fb63ed64904 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/libQtCore.so.4
#26 0x00007fb63ed66ab9 in QCoreApplication::exec() () from /usr/lib/libQtCore.so.4
#27 0x0000000000403f47 in _start ()

Reported using DrKonqi