Version:            (using KDE 4.2.0)
Compiler:          gcc version 4.3.2 20081105 (Red Hat 4.3.2-7) (GCC) 
OS:                Linux
Installed from:    Fedora RPMs

I came across a webpage that crashed Konqueror. Upon investigation and localization, it appears to be caused by some non-ascii characters in a script tag. I'm not sure if they're supposed to be unicode, but they repeatedly cause the KJS debugger to crash (as can be seen from the backtrace below). Switching the js debugger off prevents the crash and the icon on the status bar says it detected invalid characters. I will in a moment attach a very small html file which triggers the crash when the debugger is on.

Backtrace:
Application: Konqueror (konqueror), signal SIGSEGV
0x00000034c10a7f81 in nanosleep () from /lib64/libc.so.6
[Current thread is 1 (Thread 0x7f7d17ae0800 (LWP 16371))]

Thread 1 (Thread 0x7f7d17ae0800 (LWP 16371)):
[KCrash Handler]
#5  0x000000343e462980 in KJS::Debugger::reportSourceParsed () from /usr/lib64/libkjs.so.4
#6  0x000000343e468277 in KJS::Interpreter::evaluate () from /usr/lib64/libkjs.so.4
#7  0x000000343e4686a3 in KJS::Interpreter::evaluate () from /usr/lib64/libkjs.so.4
#8  0x000000343f0264b3 in ?? () from /usr/lib64/libkhtml.so.5
#9  0x000000343edddfb1 in KHTMLPart::executeScript () from /usr/lib64/libkhtml.so.5
#10 0x000000343ee8cb68 in ?? () from /usr/lib64/libkhtml.so.5
#11 0x000000343ee91d88 in ?? () from /usr/lib64/libkhtml.so.5
#12 0x000000343ee93955 in ?? () from /usr/lib64/libkhtml.so.5
#13 0x000000343ee95e4a in ?? () from /usr/lib64/libkhtml.so.5
#14 0x000000343ee96c53 in ?? () from /usr/lib64/libkhtml.so.5
#15 0x000000343edda739 in KHTMLPart::write () from /usr/lib64/libkhtml.so.5
#16 0x000000343edda614 in KHTMLPart::end () from /usr/lib64/libkhtml.so.5
#17 0x000000343ede6332 in KHTMLPart::slotFinished () from /usr/lib64/libkhtml.so.5
#18 0x000000343edffaa9 in KHTMLPart::qt_metacall () from /usr/lib64/libkhtml.so.5
#19 0x0000003eb3356764 in QMetaObject::activate (sender=0x7f7d0b1c6380, from_signal_index=<value optimized out>, to_signal_index=7, argv=0x7fff1fb26250) at kernel/qobject.cpp:3031
#20 0x0000003438ee8db2 in KJob::result () from /usr/lib64/libkdecore.so.5
#21 0x0000003438ee912f in KJob::emitResult () from /usr/lib64/libkdecore.so.5
#22 0x0000003439ee4e40 in KIO::SimpleJob::slotFinished () from /usr/lib64/libkio.so.5
#23 0x0000003439ee63d3 in KIO::TransferJob::slotFinished () from /usr/lib64/libkio.so.5
#24 0x0000003439ee7415 in KIO::TransferJob::qt_metacall () from /usr/lib64/libkio.so.5
#25 0x0000003eb3356764 in QMetaObject::activate (sender=0x9d1630, from_signal_index=<value optimized out>, to_signal_index=8, argv=0x7fff1fb26250) at kernel/qobject.cpp:3031
#26 0x0000003439f8e311 in KIO::SlaveInterface::dispatch () from /usr/lib64/libkio.so.5
#27 0x0000003439f8bf32 in KIO::SlaveInterface::dispatch () from /usr/lib64/libkio.so.5
#28 0x0000003439f7f3fe in KIO::Slave::gotInput () from /usr/lib64/libkio.so.5
#29 0x0000003439f7f708 in KIO::Slave::qt_metacall () from /usr/lib64/libkio.so.5
#30 0x0000003eb3356764 in QMetaObject::activate (sender=0x7f7d0cd49850, from_signal_index=<value optimized out>, to_signal_index=4, argv=0x7fff1fb26250) at kernel/qobject.cpp:3031
#31 0x0000003439eb78d1 in ?? () from /usr/lib64/libkio.so.5
#32 0x0000003439eb7f7a in KIO::Connection::qt_metacall () from /usr/lib64/libkio.so.5
#33 0x0000003eb33513d5 in QObject::event (this=0x7f7d0cd49850, e=0x7f7d0cdaa160) at kernel/qobject.cpp:1155
#34 0x0000003720d828dd in QApplicationPrivate::notify_helper (this=0x8ff920, receiver=0x7f7d0cd49850, e=0x7f7d0cdaa160) at kernel/qapplication.cpp:3803
#35 0x0000003720d8a68a in QApplication::notify (this=0x7fff1fb28740, receiver=0x7f7d0cd49850, e=0x7f7d0cdaa160) at kernel/qapplication.cpp:3768
#36 0x0000003439604deb in KApplication::notify () from /usr/lib64/libkdeui.so.5
#37 0x0000003eb3342391 in QCoreApplication::notifyInternal (this=0x7fff1fb28740, receiver=0x7f7d0cd49850, event=0x7f7d0cdaa160) at kernel/qcoreapplication.cpp:587
#38 0x0000003eb334302a in QCoreApplication::sendEvent () at ../../src/corelib/kernel/qcoreapplication.h:209
#39 QCoreApplicationPrivate::sendPostedEvents (receiver=0x0, event_type=0, data=0x8e7f90) at kernel/qcoreapplication.cpp:1198
#40 0x0000003eb336ab13 in QCoreApplication::sendPostedEvents () at ../../src/corelib/kernel/qcoreapplication.h:214
#41 postEventSourceDispatch (s=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:205
#42 0x0000003eb263779b in g_main_context_dispatch () from /lib64/libglib-2.0.so.0
#43 0x0000003eb263af6d in ?? () from /lib64/libglib-2.0.so.0
#44 0x0000003eb263b12b in g_main_context_iteration () from /lib64/libglib-2.0.so.0
#45 0x0000003eb336a79f in QEventDispatcherGlib::processEvents (this=0x8ff0f0, flags=<value optimized out>) at kernel/qeventdispatcher_glib.cpp:319
#46 0x0000003720e1328f in QGuiEventDispatcherGlib::processEvents (this=0x7f7d0cd581d0, flags=<value optimized out>) at kernel/qguieventdispatcher_glib.cpp:198
#47 0x0000003eb3340cb2 in QEventLoop::processEvents (this=<value optimized out>, flags=) at kernel/qeventloop.cpp:143
#48 0x0000003eb3340e3d in QEventLoop::exec (this=0x7fff1fb284e0, flags=) at kernel/qeventloop.cpp:194
#49 0x0000003eb33432ed in QCoreApplication::exec () at kernel/qcoreapplication.cpp:845
#50 0x000000343acb8af9 in kdemain () from /usr/lib64/libkdeinit4_konqueror.so
#51 0x00000034c101e576 in __libc_start_main (main=0x400820 <_start+240>, argc=2, ubp_av=0x7fff1fb290b8, init=0x400850 <__libc_csu_init>, fini=<value optimized out>, rtld_fini=<value optimized out>, 
    stack_end=0x7fff1fb290a8) at libc-start.c:220
#52 0x0000000000400759 in _start ()