Version:            (using KDE KDE 3.5.5)
Installed from:    Debian testing/unstable Packages

KMail just crashed on me while syncing a dIMAP account.  While it was syncing, I changed the view to a different folder, and then clicked on a message in the folder, and then KMail crashed.  Here is the backtrace.  I haven't restarted KMail yet, so I really hope I haven't lost any mail.

(And so begins the refiling of dIMAP bugs.  :) )

Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1208387904 (LWP 13519)]
[New Thread -1239381072 (LWP 13529)]
[New Thread -1230988368 (LWP 13528)]
[New Thread -1222595664 (LWP 13527)]
[New Thread -1214202960 (LWP 13526)]
[KCrash handler]
#9  KMAcctCachedImap::processNewMail (this=0x818d6d0, folder=0x0, 
    recurse=true) at /usr/share/qt3/include/qvaluelist.h:446
#10 0x4f2f7ec1 in KMAcctCachedImap::processNewMail (this=0x818d6d0)
    at /tmp/buildd/kdepim-3.5.5.dfsg.1/./kmail/kmacctcachedimap.cpp:215
#11 0x4f322130 in KMail::AccountManager::processNextCheck (this=0x83400b0, 
    _newMail=false)
    at /tmp/buildd/kdepim-3.5.5.dfsg.1/./kmail/accountmanager.cpp:197
#12 0x4f3222de in KMail::AccountManager::singleCheckMail (this=0x83400b0, 
    account=0x818d6d0, interactive=false)
    at /tmp/buildd/kdepim-3.5.5.dfsg.1/./kmail/accountmanager.cpp:125
#13 0x4f32294e in KMAccount::mailCheck (this=0x818d6d0)
    at /tmp/buildd/kdepim-3.5.5.dfsg.1/./kmail/kmaccount.cpp:384
#14 0x4f229f55 in KMAccount::qt_invoke (this=0x818d6d0, _id=2, _o=0xbfc276ac)
    at ./kmaccount.moc:237
#15 0x4f229feb in KMail::NetworkAccount::qt_invoke (this=0x818d6d0, _id=2, 
    _o=0xbfc276ac) at ./networkaccount.moc:77
#16 0x4f4b8393 in KMail::ImapAccountBase::qt_invoke (this=0x818d6d0, _id=2, 
    _o=0xbfc276ac) at ./imapaccountbase.moc:296
#17 0x4f4b85c3 in KMAcctCachedImap::qt_invoke (this=0x818d6d0, _id=2, 
    _o=0xbfc276ac) at ./kmacctcachedimap.moc:97
#18 0x4dabc2ef in QObject::activate_signal (this=0x84646e8, clist=0x86324f8, 
    o=0xbfc276ac) at kernel/qobject.cpp:2356
#19 0x4dabcd80 in QObject::activate_signal (this=0x84646e8, signal=2)
    at kernel/qobject.cpp:2325
#20 0x4de473f2 in QTimer::timeout (this=0x84646e8)
    at .moc/debug-shared-mt/moc_qtimer.cpp:82
#21 0x4dae3ba3 in QTimer::event (this=0x84646e8, e=0xbfc279f8)
    at kernel/qtimer.cpp:219
#22 0x4da541c6 in QApplication::internalNotify (this=0xbfc27c84, 
    receiver=0x84646e8, e=0xbfc279f8) at kernel/qapplication.cpp:2635
#23 0x4da55fe3 in QApplication::notify (this=0xbfc27c84, receiver=0x84646e8, 
    e=0xbfc279f8) at kernel/qapplication.cpp:2358
#24 0x4e155f8e in KApplication::notify (this=0xbfc27c84, receiver=0x84646e8, 
    event=0xbfc279f8)
    at /home/ana/Debian/kdelibs/kdelibs-3.5.5a.dfsg.1/./kdecore/kapplication.cpp:550
#25 0x4d9e79c1 in QApplication::sendEvent (receiver=0x84646e8, 
    event=0xbfc279f8) at ../include/qapplication.h:520
#26 0x4da46bc3 in QEventLoop::activateTimers (this=0x80afa08)
    at kernel/qeventloop_unix.cpp:556
#27 0x4d9fbd0f in QEventLoop::processEvents (this=0x80afa08, flags=4)
    at kernel/qeventloop_x11.cpp:389
#28 0x4da6e719 in QEventLoop::enterLoop (this=0x80afa08)
    at kernel/qeventloop.cpp:198
#29 0x4da6e53a in QEventLoop::exec (this=0x80afa08)
    at kernel/qeventloop.cpp:145
#30 0x4da55d5f in QApplication::exec (this=0xbfc27c84)
    at kernel/qapplication.cpp:2758
#31 0x0804a094 in main (argc=0, argv=0x19)
    at /tmp/buildd/kdepim-3.5.5.dfsg.1/./kmail/main.cpp:110
#32 0x48cb4ea8 in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#33 0x08049e11 in _start () at ../sysdeps/i386/elf/start.S:119