Version:           1.1 (using 4.1.1 (KDE 4.1.1), Kubuntu packages)
Compiler:          cc
OS:                Linux (i686) release 2.6.26-5-generic

Originally reported here: https://launchpad.net/bugs/268975

Enabling preview mode while in column mode causes an assertion followed by a crash.

To reproduce:
-Start Dolphin in either icons or details mode
-Change to columns mode
-Enable previews

This will cause the following assert: 

ASSERT: "listers.isEmpty() || killed" in file /build/buildd/kde4libs-4.1.1+really4.1.1/kio/kio/kdirlister.cpp, line 581


Which results in the following backtrace:


Application: Dolphin (dolphin), signal SIGABRT
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 0xb5f9c6c0 (LWP 8091)]
[KCrash handler]
#6  0xb8093424 in __kernel_vsyscall ()
#7  0xb6826860 in raise () from /lib/tls/i686/cmov/libc.so.6
#8  0xb6828228 in abort () from /lib/tls/i686/cmov/libc.so.6
#9  0xb75fe725 in qt_message_output () from /usr/lib/libQtCore.so.4
#10 0xb75fe802 in qFatal () from /usr/lib/libQtCore.so.4
#11 0xb75fe8a5 in qt_assert () from /usr/lib/libQtCore.so.4
#12 0xb7e4d238 in KDirListerCache::updateDirectory (this=0x981d820, 
    _dir=@0xa9c7938)
    at /build/buildd/kde4libs-4.1.1+really4.1.1/kio/kio/kdirlister.cpp:581
#13 0xb7e4dba7 in KDirListerCache::emitItemsFromCache (this=0x981d820, 
    lister=0xa9412d8, items=@0xa9c7940, rootItem=@0xa9c7944, _url=@0xa9c7938, 
    _reload=true, _emitCompleted=true)
    at /build/buildd/kde4libs-4.1.1+really4.1.1/kio/kio/kdirlister.cpp:289
#14 0xb7e4dd05 in KDirLister::Private::CachedItemsJob::done (this=0xa9c7928)
    at /build/buildd/kde4libs-4.1.1+really4.1.1/kio/kio/kdirlister.cpp:251
#15 0xb7e4de55 in KDirLister::Private::CachedItemsJob::qt_metacall (
    this=0xa9c7928, _c=QMetaObject::InvokeMetaMethod, _id=0, _a=0x9b2ea40)
    at /build/buildd/kde4libs-4.1.1+really4.1.1/obj-i486-linux-gnu/kio/kdirlister_p.moc:154
#16 0xb770495b in QMetaCallEvent::placeMetaCall ()
   from /usr/lib/libQtCore.so.4
#17 0xb77064f1 in QObject::event () from /usr/lib/libQtCore.so.4
#18 0xb6c9dbfc in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#19 0xb6ca5a6e in QApplication::notify () from /usr/lib/libQtGui.so.4
#20 0xb7bc519d in KApplication::notify (this=0xbffadff4, receiver=0xa9c7928, 
    event=0xa968b60)
    at /build/buildd/kde4libs-4.1.1+really4.1.1/kdeui/kernel/kapplication.cpp:311
#21 0xb76f6bbf in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#22 0xb76f7845 in QCoreApplicationPrivate::sendPostedEvents ()
   from /usr/lib/libQtCore.so.4
#23 0xb76f7a3d in QCoreApplication::sendPostedEvents ()
   from /usr/lib/libQtCore.so.4
#24 0xb77215bf in ?? () from /usr/lib/libQtCore.so.4
#25 0xb63576b1 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#26 0xb635ad53 in ?? () from /usr/lib/libglib-2.0.so.0
#27 0xb635af11 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#28 0xb7721208 in QEventDispatcherGlib::processEvents ()
   from /usr/lib/libQtCore.so.4
#29 0xb6d37b45 in ?? () from /usr/lib/libQtGui.so.4
#30 0xb76f528a in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#31 0xb76f544a in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#32 0xb76f7b05 in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#33 0xb6c9da77 in QApplication::exec () from /usr/lib/libQtGui.so.4
#34 0x0808515f in _start ()
#0  0xb8093424 in __kernel_vsyscall ()