Version:           1.10.0, KDE 4.1.1 (KDE 4.1.0 (4.1 >= 20080722)) "release 40.1" (using KDE 4.1.0)
OS:                Linux
Installed from:    SuSE RPMs

I'd run "cleanlinks" program and it deleted some folders belong to KMail (in ~/.kde4/share/apps/kmail/mail/)

After the following IMAP sync it recognized that some of its folders are missing and showed me a MessageBox about it.
But then it crashed.

Here is the crashlog:
Alkalmazás: KMail (kmail), szignál: SIGSEGV
[?1034h[Thread debugging using libthread_db enabled]
[New Thread 0xb47e16d0 (LWP 3630)]
[New Thread 0xb0a3eb90 (LWP 23364)]
[KCrash handler]
#5  0xb7b61756 in KMFolderCachedImap::findByUID (this=0x829a090, uid=54)
    at /usr/src/debug/kdepim-4.1.0/kmail/kmfoldercachedimap.cpp:586
#6  0xb7b70f97 in KMFolderCachedImap::slotGetMessagesData (this=0x829a090, 
    job=0x87ef798, data=@0xbffe5c54)
    at /usr/src/debug/kdepim-4.1.0/kmail/kmfoldercachedimap.cpp:1705
#7  0xb7b778be in KMFolderCachedImap::qt_metacall (this=0x829a090, 
    _c=QMetaObject::InvokeMetaMethod, _id=3, _a=0xbffe59d8)
    at /usr/src/debug/kdepim-4.1.0/build/kmail/kmfoldercachedimap.moc:195
#8  0xb5f2ad7a in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#9  0xb5f2b2f2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#10 0xb67589d9 in KIO::TransferJob::data () from /usr/lib/libkio.so.5
#11 0xb6759312 in KIO::TransferJob::slotData () from /usr/lib/libkio.so.5
#12 0xb6760a35 in KIO::TransferJob::qt_metacall () from /usr/lib/libkio.so.5
#13 0xb5f2ad7a in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#14 0xb5f2b2f2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#15 0xb6809f13 in KIO::SlaveInterface::data () from /usr/lib/libkio.so.5
#16 0xb680c9d4 in KIO::SlaveInterface::dispatch () from /usr/lib/libkio.so.5
#17 0xb680a6a7 in KIO::SlaveInterface::dispatch () from /usr/lib/libkio.so.5
#18 0xb67fd320 in KIO::Slave::gotInput () from /usr/lib/libkio.so.5
#19 0xb67fd693 in KIO::Slave::qt_metacall () from /usr/lib/libkio.so.5
#20 0xb5f2ad7a in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#21 0xb5f2b2f2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#22 0xb672eb37 in KIO::Connection::readyRead () from /usr/lib/libkio.so.5
#23 0xb6730563 in ?? () from /usr/lib/libkio.so.5
#24 0xb6730bb6 in KIO::Connection::qt_metacall () from /usr/lib/libkio.so.5
#25 0xb5f25c9b in QMetaCallEvent::placeMetaCall () from /usr/lib/libQtCore.so.4
#26 0xb5f27841 in QObject::event () from /usr/lib/libQtCore.so.4
#27 0xb535f2dc in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#28 0xb53656fe in QApplication::notify () from /usr/lib/libQtGui.so.4
#29 0xb652eb0d in KApplication::notify () from /usr/lib/libkdeui.so.5
#30 0xb5f194a1 in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#31 0xb5f19d61 in QCoreApplicationPrivate::sendPostedEvents ()
   from /usr/lib/libQtCore.so.4
#32 0xb5f19efd in QCoreApplication::sendPostedEvents ()
   from /usr/lib/libQtCore.so.4
#33 0xb53e986f in ?? () from /usr/lib/libQtGui.so.4
#34 0xb5f17bfa in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#35 0xb5f17dba in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#36 0xb5f19fbd in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#37 0xb535f157 in QApplication::exec () from /usr/lib/libQtGui.so.4
#38 0x0804a880 in main (argc=141499112, argv=0x87eaa78)
    at /usr/src/debug/kdepim-4.1.0/kmail/main.cpp:146
#0  0xffffe430 in __kernel_vsyscall ()