Version:            (using Devel)

Reproduce by:
right click in feeds list on folder
Add new feed
Paste url in dialog, Ok
Ok feed settings with default options
Then click any story in the newly fetched feed.

Console output:
kded(20612)/kio (KPasswdServer) KPasswdServer::checkAuthInfo: KPasswdServer::checkAuthInfo: User=  "" , WindowId =  0
akregator(20903)/kio (KIOJob) KIO::SlaveInterface::dispatch: incoming metadata now QMap(("cache-creation-date", "1204760550")("expire-date", "1204760792")("modified", "Wed, 05 Mar 2008 23:42:01 GMT")("referrer", "")("request-id", "")("ssl_in_use", "FALSE")) 
 newly arrived metadata is QMap(("cache-creation-date", "1204760550")("expire-date", "1204760792")("modified", "Wed, 05 Mar 2008 23:42:01 GMT")("referrer", "")("request-id", "")("ssl_in_use", "FALSE"))
akregator(20903) Akregator::Backend::FeedStorageMK4Impl::FeedStorageMK4Impl: "http://www.osnews.com/files/recent.xml"
akregator(20903) Akregator::ArticleListView::setArticleModel: 0
akregator(20903) Akregator::ArticleListView::setArticleModel: 1
akregator(20903) Akregator::ArticleListView::setArticleModel: 2
akregator(20903) Akregator::ArticleListView::setArticleModel: 3
akregator(20903) Akregator::ArticleListView::setArticleModel: 0   100
akregator(20903) Akregator::ArticleListView::setArticleModel: 1   100
akregator(20903) Akregator::ArticleListView::setArticleModel: 2   100
akregator(20903) Akregator::ArticleListView::setArticleModel: 3   397
akregator: /space/kde/sources/trunk/KDE/kdepim/akregator/src/articlemodel.cpp:226: void Akregator::ArticleModel::Private::articlesUpdated(Akregator::TreeNode*, const QList<Akregator::Article>&): Assertion `row != -1' failed.
KCrash: crashing... crashRecursionCounter = 2
KCrash: Application Name = akregator path = <unknown> pid = 20903
sock_file=/home/testuser/.kde4/socket-gorse/kdeinit4__1

Backtrace:
Application: Akregator (akregator), signal SIGABRT
[?1034hUsing host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 0xb4fc38e0 (LWP 20619)]
[KCrash handler]
#6  0xffffe410 in __kernel_vsyscall ()
#7  0xb552a8f5 in raise () from /lib/libc.so.6
#8  0xb552c1e1 in abort () from /lib/libc.so.6
#9  0xb5523c1e in __assert_fail () from /lib/libc.so.6
#10 0xb36227f2 in Akregator::ArticleModel::Private::articlesUpdated (
    this=0x838e730, node=0x87d2b20, list=@0xbfb04e48)
    at /space/kde/sources/trunk/KDE/kdepim/akregator/src/articlemodel.cpp:226
#11 0xb3622d95 in Akregator::ArticleModel::qt_metacall (this=0x82625c0, 
    _c=QMetaObject::InvokeMetaMethod, _id=2, _a=0xbfb04cf8)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/articlemodel.moc:73
#12 0xb7e3d8ea in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#13 0xb7e3dd32 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#14 0xb362ce31 in Akregator::TreeNode::signalArticlesUpdated (this=0x82d57b8, 
    _t1=0x87d2b20, _t2=@0xbfb04e48)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/treenode.moc:123
#15 0xb362d146 in Akregator::TreeNode::qt_metacall (this=0x82d57b8, 
    _c=QMetaObject::InvokeMetaMethod, _id=3, _a=0xbfb04e08)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/treenode.moc:87
#16 0xb362eb7e in Akregator::Folder::qt_metacall (this=0x82d57b8, 
    _c=QMetaObject::InvokeMetaMethod, _id=7, _a=0xbfb04e08)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/folder.moc:78
#17 0xb7e3d8ea in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#18 0xb7e3dd32 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#19 0xb362ce31 in Akregator::TreeNode::signalArticlesUpdated (this=0x87d2b20, 
    _t1=0x87d2b20, _t2=@0xbfb04e48)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/treenode.moc:123
#20 0xb3625486 in Akregator::Feed::doArticleNotification (this=0x87d2b20)
    at /space/kde/sources/trunk/KDE/kdepim/akregator/src/feed.cpp:798
#21 0xb362cfab in Akregator::TreeNode::setNotificationMode (this=0x87d2b20, 
    doNotify=true)
    at /space/kde/sources/trunk/KDE/kdepim/akregator/src/treenode.cpp:180
#22 0xb361c5bb in Akregator::ArticleModifyJob::doStart (this=0x87c3540)
    at /space/kde/sources/trunk/KDE/kdepim/akregator/src/articlejobs.cpp:131
#23 0xb361c703 in Akregator::ArticleModifyJob::qt_metacall (this=0x87c3540, 
    _c=QMetaObject::InvokeMetaMethod, _id=0, _a=0xbfb04fb8)
    at /space/kde/builds/trunk/KDE/kdepim/akregator/src/articlejobs.moc:116
#24 0xb7e3d8ea in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#25 0xb7e3dd32 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#26 0xb7e45ea7 in QSingleShotTimer::timeout () from /usr/lib/libQtCore.so.4
#27 0xb7e45fcc in QSingleShotTimer::timerEvent () from /usr/lib/libQtCore.so.4
#28 0xb7e3c7b4 in QObject::event () from /usr/lib/libQtCore.so.4
#29 0xb59a47cc in QApplicationPrivate::notify_helper ()
   from /usr/lib/libQtGui.so.4
#30 0xb59ab7a9 in QApplication::notify () from /usr/lib/libQtGui.so.4
#31 0xb7988d73 in KApplication::notify (this=0xbfb056dc, receiver=0x8792370, 
    event=0xbfb05488)
    at /space/kde/sources/trunk/KDE/kdelibs/kdeui/kernel/kapplication.cpp:311
#32 0xb7e2d389 in QCoreApplication::notifyInternal ()
   from /usr/lib/libQtCore.so.4
#33 0xb7e54d21 in QTimerInfoList::activateTimers ()
   from /usr/lib/libQtCore.so.4
#34 0xb7e54e15 in QEventDispatcherUNIX::activateTimers ()
   from /usr/lib/libQtCore.so.4
#35 0xb7e55e5b in QEventDispatcherUNIX::processEvents ()
   from /usr/lib/libQtCore.so.4
#36 0xb5a29e81 in QEventDispatcherX11::processEvents ()
   from /usr/lib/libQtGui.so.4
#37 0xb7e2c61d in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#38 0xb7e2c7b1 in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#39 0xb7e2e8fa in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#40 0xb59a3ec7 in QApplication::exec () from /usr/lib/libQtGui.so.4
#41 0x080500b5 in main (argc=5, argv=0xbfb057b4)
    at /space/kde/sources/trunk/KDE/kdepim/akregator/src/main.cpp:115
#0  0xffffe410 in __kernel_vsyscall ()