Version:           1.2 (using KDE KDE 3.5.0)
Installed from:    Unlisted Binary Package
OS:                Linux

Using an 3.4.3's ~/.kde/share/apps/kmail/imap directory, kontact crashed after upgrading to KDE 3.5.0.
- I observed that a nested imap directory was absent from the listing of directories before it crashed.
- Seems it crashed when checking for new mail
- I was not able to reproduce it on another 3.4.3 box that I also upgraded to 3.5.0
- The workaround was to delete ~/.kde/share/apps/kmail/imap; then no more crash.

I have two backtraces, looking identical and leaving to KMFolder::noContent () from /usr/lib/libkmailprivate.so.

Full backtrace is:

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Using host libthread_db library "/lib/tls/libthread_db.so.1".
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`system-supplied DSO at 0xffffe000' has disappeared; keeping its symbols.
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[Thread debugging using libthread_db enabled]
[New Thread -1241913664 (LWP 5868)]
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[KCrash handler]
#3  0xb5583a6c in KMFolder::noContent () from /usr/lib/libkmailprivate.so
#4  0xb5615479 in KMAcctImap::processNewMail ()
   from /usr/lib/libkmailprivate.so
#5  0xb55b756e in KMail::AccountManager::processNextCheck ()
   from /usr/lib/libkmailprivate.so
#6  0xb55b772b in KMail::AccountManager::singleCheckMail ()
   from /usr/lib/libkmailprivate.so
#7  0xb554389c in KMAccount::mailCheck () from /usr/lib/libkmailprivate.so
#8  0xb5543a5f in KMAccount::qt_invoke () from /usr/lib/libkmailprivate.so
#9  0xb56025c4 in KMail::NetworkAccount::qt_invoke ()
   from /usr/lib/libkmailprivate.so
#10 0xb560e50c in KMail::ImapAccountBase::qt_invoke ()
   from /usr/lib/libkmailprivate.so
#11 0xb56166cc in KMAcctImap::qt_invoke () from /usr/lib/libkmailprivate.so
#12 0xb6fe6b57 in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#13 0xb6fe763b in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#14 0xb7378d55 in QTimer::timeout () from /usr/lib/libqt-mt.so.3
#15 0xb700c0b4 in QTimer::event () from /usr/lib/libqt-mt.so.3
#16 0xb6f7c698 in QApplication::internalNotify () from /usr/lib/libqt-mt.so.3
#17 0xb6f7c8b6 in QApplication::notify () from /usr/lib/libqt-mt.so.3
#18 0xb7676abc in KApplication::notify () from /usr/lib/libkdecore.so.4
#19 0xb6f0c5e5 in QApplication::sendEvent () from /usr/lib/libqt-mt.so.3
#20 0xb6f6d98c in QEventLoop::activateTimers () from /usr/lib/libqt-mt.so.3
#21 0xb6f2035c in QEventLoop::processEvents () from /usr/lib/libqt-mt.so.3
#22 0xb6f94da2 in QEventLoop::enterLoop () from /usr/lib/libqt-mt.so.3
#23 0xb6f94ccb in QEventLoop::exec () from /usr/lib/libqt-mt.so.3
#24 0xb6f7b225 in QApplication::exec () from /usr/lib/libqt-mt.so.3
#25 0x0805aa5d in ?? ()
#26 0xbf803050 in ?? ()
#27 0x00000001 in ?? ()
#28 0x00000001 in ?? ()
#29 0x00000000 in ?? ()