Seems that upstream they already fix it kde bug Committed on 30/09/2011 at 12:41. Pushed by argonel into branch 'master'. Changed method of remember/marker line tracking. Qt 4.7.4 introduces a change to the handling of QTextBlock::userState that makes it unusable for the purposes of tracking which block represents a marker or remember line. Previous versions of Qt also changed or otherwise corrupted the userState value causing the loss of synchronization with the data held in the IRCView itself. Blocks are now tracked via the userData field, which was unmolested in the change made to QTextDocument. Warning: this commit introduces a large volume of debugging output. For more information about the Qt change, see QTBUG-20916. BUG: 210106 CCBUG: 260598 Fixes are in http://commits.kde.org/konversation/cbe876c954b5deaf1a6729b7123d6880df4513ee Attached the backtrace I get -- Bruno Friedmann Ioda-Net Sàrl www.ioda-net.ch openSUSE Member & Ambassador GPG KEY : D5C9B751C4653227 irc: tigerfoot