Version:           2.0.80 (using 4.00.60 (KDE 4.0.60 >= 20080129), Gentoo)
Compiler:          i686-pc-linux-gnu-gcc
OS:                Linux (i686) release 2.6.23-gentoo-r6

Steps to reproduce:

1) Open kget
2) Download some file
3) Go to detailed view of that download
4) Click on "Delete Selected"
5) See kget crash with the following backtrace:

Application: KGet (kget), signal SIGABRT
Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 0xb64d16d0 (LWP 8469)]
[KCrash handler]
#6  0xffffe410 in __kernel_vsyscall ()
#7  0xb673d1f1 in *__GI_raise (sig=6)
    at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#8  0xb673e9b8 in *__GI_abort () at abort.c:88
#9  0xb7304265 in qt_message_output (msgType=QtFatalMsg, 
    buf=0xbfcc6aec "ASSERT: \"extenderIndices.value(extender).isValid()\" in file /var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs-9999.4/kdeui/itemviews/kextendableitemdelegate.cpp, line 116") at global/qglobal.cpp:2160
#10 0xb730432a in qFatal (msg=0xb740b87c "ASSERT: \"%s\" in file %s, line %d")
    at global/qglobal.cpp:2392
#11 0xb7304555 in qt_assert (
    assertion=0xb7f34224 "extenderIndices.value(extender).isValid()", 
    file=0xb7f341b8 "/var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs-9999.4/kdeui/itemviews/kextendableitemdelegate.cpp", line=116)
    at global/qglobal.cpp:1917
#12 0xb7deb82c in KExtendableItemDelegate::Private::_k_extenderDestructionHandler (this=0x81ea5d8, destroyed=0x8490228)
    at /var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs-9999.4/kdeui/itemviews/kextendableitemdelegate.cpp:116
#13 0xb7deb9e0 in KExtendableItemDelegate::qt_metacall (this=0x81ea780, 
    _c=QMetaObject::InvokeMetaMethod, _id=2, _a=0xbfcc90cc)
    at /var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs_build/kdeui/kextendableitemdelegate.moc:73
#14 0x0806f29f in TransfersViewDelegate::qt_metacall (this=0x81ea780, 
    _c=QMetaObject::InvokeMetaMethod, _id=11, _a=0xbfcc90cc)
    at /var/tmp/portage/kde-base/kdenetwork-9999.4/work/kdenetwork_build/kget/transfersviewdelegate.moc:158
#15 0xb73ea1f4 in QMetaObject::activate (sender=0x8490228, 
    from_signal_index=0, to_signal_index=1, argv=<value optimized out>)
    at kernel/qobject.cpp:3081
#16 0xb73ea5e2 in QMetaObject::activate (sender=0x8490228, m=0x8093040, 
    from_local_signal_index=0, to_local_signal_index=1, argv=0xbfcc90cc)
    at kernel/qobject.cpp:3160
#17 0xb73ea66a in QObject::destroyed (this=0x8490228, _t1=0x8490228)
    at .moc/debug-shared/moc_qobject.cpp:114
#18 0xb73eab51 in ~QObject (this=0x8490228) at kernel/qobject.cpp:802
#19 0xb6ac164b in ~QWidget (this=0x8490228) at kernel/qwidget.cpp:1210
#20 0xb6e0ef75 in ~QGroupBox (this=0x8490228) at widgets/qgroupbox.cpp:211
#21 0xb73e7fd7 in QObject::event (this=0x8490228, e=0x2115)
    at kernel/qobject.cpp:1105
#22 0xb6acafe2 in QWidget::event (this=0x8490228, event=0x83382b8)
    at kernel/qwidget.cpp:6510
#23 0xb6e11068 in QGroupBox::event (this=0x8490228, e=0x83382b8)
    at widgets/qgroupbox.cpp:394
#24 0xb6a78e8a in QApplicationPrivate::notify_helper (this=0x80a6cb8, 
    receiver=0x8490228, e=0x83382b8) at kernel/qapplication.cpp:3556
#25 0xb6a7a6df in QApplication::notify (this=0xbfcc9a90, receiver=0x8490228, 
    e=0x83382b8) at kernel/qapplication.cpp:3115
#26 0xb7e09763 in KApplication::notify (this=0xbfcc9a90, receiver=0x8490228, 
    event=0x83382b8)
    at /var/tmp/portage/kde-base/kdelibs-9999.4/work/kdelibs-9999.4/kdeui/kernel/kapplication.cpp:311
#27 0xb73d6d7b in QCoreApplication::notifyInternal (this=0xbfcc9a90, 
    receiver=0x8490228, event=0x83382b8) at kernel/qcoreapplication.cpp:530
#28 0xb73d821a in QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, 
    event_type=0, data=0x8095f58) at kernel/qcoreapplication.h:200
#29 0xb7400905 in QEventDispatcherUNIX::processEvents (this=0x80a5e10, 
    flags=@0xbfcc9988) at kernel/qeventdispatcher_unix.cpp:858
#30 0xb6b02cce in QEventDispatcherX11::processEvents (this=0x80a5e10, 
    flags=@0xbfcc99b4) at kernel/qeventdispatcher_x11.cpp:145
#31 0xb73d6191 in QEventLoop::processEvents (this=0xbfcc9a20, 
    flags=@0xbfcc99e8) at kernel/qeventloop.cpp:140
#32 0xb73d629a in QEventLoop::exec (this=0xbfcc9a20, flags=@0xbfcc9a28)
    at kernel/qeventloop.cpp:186
#33 0xb73d8626 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:759
#34 0xb6a78487 in QApplication::exec () at kernel/qapplication.cpp:3053
#35 0x08088158 in main (argc=2, argv=0xbfcc9c44)
    at /var/tmp/portage/kde-base/kdenetwork-9999.4/work/kdenetwork-9999.4/kget/main.cpp:150
#36 0xb6729fdc in __libc_start_main (main=0x8087810 <main>, argc=2, 
    ubp_av=0xbfcc9c44, init=0x8088a70 <__libc_csu_init>, 
    fini=0x8088a60 <__libc_csu_fini>, rtld_fini=0xb7f76100 <_dl_fini>, 
    stack_end=0xbfcc9c3c) at libc-start.c:229
#37 0x0805f561 in _start ()
#0  0xffffe410 in __kernel_vsyscall ()