Version:           1.2.80 (using 4.2.60 (KDE 4.2.60 (KDE 4.3 >= 20090106)), MinGW 3.4.5)
Compiler:          gcc.exe
OS:                Microsoft Windows (i686) release 5.1 (XP Professional)

I have bookmarked all Windows' drives for convenience.
1)Open Dolphin
2)switch from Home (or whatever default location is set in Dolphin) to some bookmarked location (even the root of the same drive will do)
3)browse into some directory and maybe one more inside of that
4)go back in history (about one or two dirs back)
5)click the forward button fast
The result: dolphin will reach the latest directory in the history and hang with crash.

Tested with Windows XP SP3, MinGW svn build in RelWithDebInfo mode.

Here's a backtrace:
Starting program: X:\rel-build\bin/dolphin.exe
[New thread 460.0xfec]
[New thread 460.0x658]
[New thread 460.0x548]
warning: Lowest section in C:\WINDOWS\system32\xpsp2res.dll is .rsrc at 00011000
[New thread 460.0xf54]
[New thread 460.0x1ac]
warning: Debug:"X:/rel-build/bin/dolphin.exe(460)" Error in thread 0xfec : "org.freedesktop.DBus.Error.ServiceUnknown - The name org.kde.nepomuk.services.nepomukstorage was not provided by any .service files"

warning: Debug:"X:/rel-build/bin/dolphin.exe(460)" Error in thread 0xfec : "QLocalSocket::connectToServer: Invalid name"

[New thread 460.0xeb0]
warning: Critical:dolphin(460): Shortcut for KAction  "close_tab" "Close Tab" set with QShortcut::setShortcut()! See KAction documentation.

warning: Critical:dolphin(460): Attempt to use QAction "show_info_panel" with KXMLGUIFactory!

warning: Critical:dolphin(460): Attempt to use QAction "show_folders_panel" with KXMLGUIFactory!

warning: Critical:dolphin(460): Attempt to use QAction "show_places_panel" with
KXMLGUIFactory!


Program received signal SIGSEGV, Segmentation fault.
0x7c8097ff in KERNEL32!InterlockedIncrement ()
   from C:\WINDOWS\system32\kernel32.dll
(gdb) bt
#0  0x7c8097ff in KERNEL32!InterlockedIncrement ()
   from C:\WINDOWS\system32\kernel32.dll
#1  0x0645101b in KDirListerCache::slotResult (this=0xbdb5df8, j=0xe81abd8)
    at X:/rel-build/include/QtCore/qatomic_windows.h:395
#2  0x06466fef in KDirListerCache::qt_metacall (this=0xbdb5df8,
    _c=InvokeMetaMethod, _id=12, _a=0x22cb50)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/kdirlister_p.moc:98
#3  0x6a33d953 in ZN11QMetaObject8activateEP7QObjectiiPPv ()
   from X:\rel-build\bin\QtCore4.dll
#4  0x0111d0f8 in KJob::result (this=0xe81abd8, _t1=0xe81abd8)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kdecore/kjob.moc:186
#5  0x0111d289 in KJob::emitResult (this=0xe81abd8)
    at X:/shared/svn/trunk/KDE/kdelibs/kdecore/jobs/kjob.cpp:294
#6  0x063fef1b in KIO::SimpleJob::slotFinished (this=0xe81abd8)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/job.cpp:489
#7  0x06409237 in KIO::ListJob::slotFinished (this=0xe81abd8)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/job.cpp:2416
#8  0x06422f07 in KIO::ListJob::qt_metacall (this=0xe81abd8,
    _c=InvokeMetaMethod, _id=43, _a=0x22ce98)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/jobclasses.moc:747
#9  0x6a33d953 in ZN11QMetaObject8activateEP7QObjectiiPPv ()
   from X:\rel-build\bin\QtCore4.dll
#10 0x065514aa in KIO::SlaveInterface::finished (this=0xbd0dbd0)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/slaveinterface.moc:163
#11 0x06555b26 in KIO::SlaveInterface::dispatch (this=0xbd0dbd0, _cmd=104,
    rawdata=@0x22d1b0)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/slaveinterface.cpp:175
#12 0x065509e5 in KIO::SlaveInterface::dispatch (this=0xbd0dbd0)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/slaveinterface.cpp:91
#13 0x06533ee9 in KIO::Slave::gotInput (this=0xbd0dbd0)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/slave.cpp:322
#14 0x06534541 in KIO::Slave::qt_metacall (this=0xbd0dbd0,
    _c=InvokeMetaMethod, _id=30, _a=0x22d348)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/slave.moc:75
#15 0x6a33d953 in ZN11QMetaObject8activateEP7QObjectiiPPv ()
   from X:\rel-build\bin\QtCore4.dll
#16 0x063bbd97 in KIO::Connection::readyRead (this=0xbd25860)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/connection.moc:84
#17 0x063be573 in KIO::ConnectionPrivate::dequeue (this=0xdfe9fd8)
    at X:/shared/svn/trunk/KDE/kdelibs/kio/kio/connection.cpp:82
#18 0x063be6de in KIO::Connection::qt_metacall (this=0xbd25860,
    _c=InvokeMetaMethod, _id=5, _a=0xe840278)
    at X:/rel-build/tmp/kdelibs-20080202/work/mingw-RelWithDebInfo/kio/connection.moc:72
#19 0x6a339fd9 in ZN14QMetaCallEvent13placeMetaCallEP7QObject ()
   from X:\rel-build\bin\QtCore4.dll
#20 0x6a33e75f in ZN7QObject5eventEP6QEvent ()
   from X:\rel-build\bin\QtCore4.dll
#21 0x6510c20c in ZN19QApplicationPrivate13notify_helperEP7QObjectP6QEvent ()
   from X:\rel-build\bin\QtGui4.dll
#22 0x6510c3e7 in ZN12QApplication6notifyEP7QObjectP6QEvent ()
   from X:\rel-build\bin\QtGui4.dll
#23 0x03418d4b in KApplication::notify (this=0x22fd50, receiver=0xbd25860,
    event=0xe1a10a0)
    at X:/shared/svn/trunk/KDE/kdelibs/kdeui/kernel/kapplication.cpp:307
#24 0x6a327d1b in ZN16QCoreApplication14notifyInternalEP7QObjectP6QEvent ()
   from X:\rel-build\bin\QtCore4.dll
#25 0x6a32d627 in ZN23QCoreApplicationPrivate16sendPostedEventsEP7QObjectiP11QThreadData () from X:\rel-build\bin\QtCore4.dll
#26 0x6a35d4f5 in ZN21QEventDispatcherWin3213processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE () from X:\rel-build\bin\QtCore4.dll
#27 0x6518cbb0 in Z25qWinProcessConfigRequestsv ()
   from X:\rel-build\bin\QtGui4.dll
#28 0x6a327678 in ZN10QEventLoop13processEventsE6QFlagsINS_17ProcessEventsFlagEE () from X:\rel-build\bin\QtCore4.dll
#29 0x6a327879 in ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE ()
   from X:\rel-build\bin\QtCore4.dll
#30 0x6a32d7fb in ZN16QCoreApplication4execEv ()
   from X:\rel-build\bin\QtCore4.dll
#31 0x0043ecf6 in main (argc=1, argv=0xb6489f8)
    at X:/shared/svn/trunk/KDE/kdebase/apps/dolphin/src/main.cpp:94
(gdb)