I have seen this error with lyx version 1.5.3-1 and libqtcore4 version 4.4.0-1ubuntu5-hardy1. In my case, the error occurs when you attempt to open a file (any file). (It also, unhelpfully, tells the user to "read the bug-reporting instructions in Help->Introduction", which is also a LyX file and triggers the crash...)
On my machine (running hardy here, with backports), I ran a simple LyX session where I start the application, click "Help", then "Introduction". Here is the console output: QPaintEngine::setSystemClip: Should not be changed while engine is active QPaintEngine::setSystemClip: Should not be changed while engine is active QWidgetPrivate::beginSharedPainter: Painter is already active lyx: SIGSEGV signal caught Sorry, you have found a bug in LyX. Please read the bug-reporting instructions in Help->Introduction and send us a bug report, if necessary. Thanks ! Bye. Aborted -- [apport] lyx-qt crashed with SIGSEGV https://bugs.launchpad.net/bugs/112259 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs