Version:           1.2.50 (using 4.00.61 (KDE 4.0.61 >= 20080207), compiled sources)
Compiler:          gcc
OS:                Linux (i686) release 2.6.24-7-generic

kdepim revision : 773563

I chose to display articles by date, so that the latest one appears at top of the list.
In this configuration, the article at top cannot be read directly : I have to click on another article in the list then click back on the latest one to read it.

The crash happens when I delete this _new_ article : 

Application: Kontact (kontact), signal SIGSEGV
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread 0xb53fca20 (LWP 7373)]
[KCrash handler]
#6  0xb12d05a9 in Akregator::Feed::xmlUrl ()
   from /opt/kde4/lib/kde4/akregatorpart.so
#7  0xb132c4c4 in Akregator::MainWidget::slotArticleSelected ()
   from /opt/kde4/lib/kde4/akregatorpart.so
#8  0xb132ea3a in Akregator::MainWidget::qt_metacall ()
   from /opt/kde4/lib/kde4/akregatorpart.so
#9  0xb7f0ecb4 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#10 0xb7f0f882 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#11 0xb12c5fb3 in Akregator::AbstractSelectionController::currentArticleChanged () from /opt/kde4/lib/kde4/akregatorpart.so
#12 0xb12e5805 in Akregator::SelectionController::currentArticleIndexChanged
    () from /opt/kde4/lib/kde4/akregatorpart.so
#13 0xb12e6505 in Akregator::SelectionController::qt_metacall ()
   from /opt/kde4/lib/kde4/akregatorpart.so
#14 0xb7f0ecb4 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#15 0xb7f0f882 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#16 0xb743cc89 in QItemSelectionModel::currentRowChanged ()
   from /usr/lib/libQtGui.so.4
#17 0xb7443ef5 in ?? () from /usr/lib/libQtGui.so.4
#18 0x08d436c0 in ?? ()
#19 0xb7f794f8 in ?? () from /usr/lib/libQtCore.so.4
#20 0xbff49b70 in ?? ()
#21 0xb742d31f in QTreeView::rowsAboutToBeRemoved ()
   from /usr/lib/libQtGui.so.4
#22 0xb74453e8 in QItemSelectionModel::qt_metacall ()
   from /usr/lib/libQtGui.so.4
#23 0xb7f0ecb4 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#24 0xb7f0f882 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#25 0xb7f2c42f in QAbstractItemModel::rowsAboutToBeRemoved ()
   from /usr/lib/libQtCore.so.4
#26 0xb7ef4b23 in QAbstractItemModel::beginRemoveRows ()
   from /usr/lib/libQtCore.so.4
#27 0xb746eb70 in ?? () from /usr/lib/libQtGui.so.4
#28 0x09047a30 in ?? ()
#29 0xbff4a194 in ?? ()
#30 0x00000000 in ?? ()
#0  0xb7fa7410 in __kernel_vsyscall ()

Akregator doesn't crash if it's not a new article (but I still cannot read it)