Version:           2.1 (using KDE KDE 3.5.6)
Installed from:    Ubuntu Packages
OS:                Linux

Loaded plugins: infowidget, ipfilter, logviewer, partfileimport, scheduler, search.

I don't know how to reproduce the crash.

Here it is the backtrace, and thanks a lot for your work:

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Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
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[Thread debugging using libthread_db enabled]
[New Thread -1235351856 (LWP 6889)]
[New Thread -1252045936 (LWP 6902)]
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[KCrash handler]
#6  0xb7e3bb9b in dht::ParseRsp () from /usr/lib/libktorrent-2.1.so
#7  0xb7e3bdc2 in dht::MakeRPCMsg () from /usr/lib/libktorrent-2.1.so
#8  0xb7e30f21 in dht::RPCServer::readPacket ()
   from /usr/lib/libktorrent-2.1.so
#9  0xb7e31222 in dht::RPCServer::qt_invoke ()
   from /usr/lib/libktorrent-2.1.so
#10 0xb6e7588b in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#11 0xb6e76330 in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#12 0xb75ff04c in KNetwork::KClientSocketBase::readyRead ()
   from /usr/lib/libkdecore.so.4
#13 0xb75ff086 in KNetwork::KClientSocketBase::slotReadActivity ()
   from /usr/lib/libkdecore.so.4
#14 0xb7611143 in KNetwork::KClientSocketBase::qt_invoke ()
   from /usr/lib/libkdecore.so.4
#15 0xb76111e6 in KNetwork::KDatagramSocket::qt_invoke ()
   from /usr/lib/libkdecore.so.4
#16 0xb6e7588b in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#17 0xb6e761a2 in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#18 0xb7202877 in QSocketNotifier::activated () from /usr/lib/libqt-mt.so.3
#19 0xb6e9844a in QSocketNotifier::event () from /usr/lib/libqt-mt.so.3
#20 0xb6e0ca60 in QApplication::internalNotify () from /usr/lib/libqt-mt.so.3
#21 0xb6e0e88f in QApplication::notify () from /usr/lib/libqt-mt.so.3
#22 0xb75d0ce2 in KApplication::notify () from /usr/lib/libkdecore.so.4
#23 0xb6d9f1e9 in QApplication::sendEvent () from /usr/lib/libqt-mt.so.3
#24 0xb6dfee59 in QEventLoop::activateSocketNotifiers ()
   from /usr/lib/libqt-mt.so.3
#25 0xb6db3d07 in QEventLoop::processEvents () from /usr/lib/libqt-mt.so.3
#26 0xb6e27136 in QEventLoop::enterLoop () from /usr/lib/libqt-mt.so.3
#27 0xb6e26f46 in QEventLoop::exec () from /usr/lib/libqt-mt.so.3
#28 0xb6e0e609 in QApplication::exec () from /usr/lib/libqt-mt.so.3
#29 0x080653d6 in ?? ()
#30 0xb6626ebc in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#31 0x08064ec1 in ?? ()