Application that crashed: kmail
Version of the application: 1.12.4
KDE Version: 4.3.4 (KDE 4.3.4)
Qt Version: 4.5.3
Operating System: Linux 2.6.31-1-686-bigmem i686
Distribution: Debian GNU/Linux 5.0.3 (lenny)

What I was doing when the application crashed:
After ISP-Reconnect, Kmail tries to reestablish IMAP-Connection and crashed immediately (Pop-Dialog opens which says: Trying to reestablish....).
I press continue and it crashes.
This happenend with Kmail pre 4.3.x, was okay with 4.3.2.
Now after I upgraded my Debian Sid box to 4.3.4 from 4.3.2 this happens again.
Thank you.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#6  KIO::Slave::deref (this=0x98ae718) at ../../kio/kio/slave.cpp:242
#7  0xb4b60bdc in KIO::Slave::gotInput (this=0x98ae718) at ../../kio/kio/slave.cpp:335
#8  0xb4b630b3 in KIO::Slave::qt_metacall (this=0x98ae718, _c=QMetaObject::InvokeMetaMethod, _id=2, _a=0xbf94d238) at ./slave.moc:76
#9  0xb6840303 in QMetaObject::activate (sender=0x9aa0678, from_signal_index=4, to_signal_index=4, argv=0x0) at kernel/qobject.cpp:3112
#10 0xb6840f42 in QMetaObject::activate (sender=0x9aa0678, m=0xb4c4c4c0, local_signal_index=0, argv=0x0) at kernel/qobject.cpp:3186
#11 0xb4a6cc07 in KIO::Connection::readyRead (this=0x9aa0678) at ./connection.moc:86
#12 0xb4a6e513 in KIO::ConnectionPrivate::dequeue (this=0x9aa0688) at ../../kio/kio/connection.cpp:82
#13 0xb4a6e8f6 in KIO::Connection::qt_metacall (this=0x9aa0678, _c=QMetaObject::InvokeMetaMethod, _id=1, _a=0x9f55ec8) at ./connection.moc:73
#14 0xb6839b0b in QMetaCallEvent::placeMetaCall (this=0x9734ef8, object=0x9aa0678) at kernel/qobject.cpp:477
#15 0xb683b5e0 in QObject::event (this=0x9aa0678, e=0x9734ef8) at kernel/qobject.cpp:1110
#16 0xb5e6aa94 in QApplicationPrivate::notify_helper (this=0x91f5e40, receiver=0x9aa0678, e=0x9734ef8) at kernel/qapplication.cpp:4065
#17 0xb5e72bee in QApplication::notify (this=0xbf94da70, receiver=0x9aa0678, e=0x9734ef8) at kernel/qapplication.cpp:3605
#18 0xb75f062d in KApplication::notify (this=0xbf94da70, receiver=0x9aa0678, event=0x9734ef8) at ../../kdeui/kernel/kapplication.cpp:302
#19 0xb682b1eb in QCoreApplication::notifyInternal (this=0xbf94da70, receiver=0x9aa0678, event=0x9734ef8) at kernel/qcoreapplication.cpp:610
#20 0xb682be2e in QCoreApplication::sendEvent (receiver=0x0, event_type=0, data=0x91cfb80) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:213
#21 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x91cfb80) at kernel/qcoreapplication.cpp:1247
#22 0xb682c00d in QCoreApplication::sendPostedEvents (receiver=0x0, event_type=0) at kernel/qcoreapplication.cpp:1140
#23 0xb68564cf in QCoreApplication::sendPostedEvents (s=0x91f80b0) at ../../include/QtCore/../../src/corelib/kernel/qcoreapplication.h:218
#24 postEventSourceDispatch (s=0x91f80b0) at kernel/qeventdispatcher_glib.cpp:276
#25 0xb3f5bf28 in g_main_context_dispatch () from /lib/libglib-2.0.so.0
#26 0xb3f5f6b3 in ?? () from /lib/libglib-2.0.so.0
#27 0xb3f5f838 in g_main_context_iteration () from /lib/libglib-2.0.so.0
#28 0xb6856041 in QEventDispatcherGlib::processEvents (this=0x91cf8d0, flags=...) at kernel/qeventdispatcher_glib.cpp:407
#29 0xb5f0a305 in QGuiEventDispatcherGlib::processEvents (this=0x91cf8d0, flags=...) at kernel/qguieventdispatcher_glib.cpp:202
#30 0xb682983a in QEventLoop::processEvents (this=0xbf94d970, flags=...) at kernel/qeventloop.cpp:149
#31 0xb6829c82 in QEventLoop::exec (this=0xbf94d970, flags=...) at kernel/qeventloop.cpp:201
#32 0xb682c0d9 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#33 0xb5e6a917 in QApplication::exec () at kernel/qapplication.cpp:3525
#34 0x0804a6e2 in main (argc=3, argv=0xbf94dc04) at ../../kmail/main.cpp:146

Reported using DrKonqi