Version:            (using KDE KDE 3.5.5)
Installed from:    Ubuntu Packages

I've replied to an e-mail with an attachment. After entering my GnuPG passphrase, KMail crashed.

The backtrace:
Using host libthread_db library "/lib/libthread_db.so.1".
[Thread debugging using libthread_db enabled]
[New Thread -1249797920 (LWP 12071)]
[New Thread -1281733744 (LWP 12076)]
[New Thread -1273345136 (LWP 12075)]
[New Thread -1264956528 (LWP 12074)]
[New Thread -1256567920 (LWP 12073)]
[KCrash handler]
#5  0xb7816a04 in memmove () from /lib/libc.so.6
#6  0xb66b403a in DwString::_copy (this=0x8c20a50)
    at /build/buildd/kdepim-3.5.5/./mimelib/dwstring.cpp:145
#7  0xb7b6ee0e in KMMessage::bodyPart (aDwBodyPart=0x8c20a28, 
    aPart=0x8c655d4, withBody=true)
    at /build/buildd/kdepim-3.5.5/./mimelib/mimelib/string.h:622
#8  0xb7ddb7b7 in (anonymous namespace)::AttachmentURLHandler::statusBarMessage (this=0x897a1f0, url=@0xbffc4554, w=0x8694308)
    at /build/buildd/kdepim-3.5.5/./kmail/partNode.h:98
#9  0xb7ddaed9 in KMail::URLHandlerManager::statusBarMessage (this=0x8971718, 
    url=@0xbffc4554, w=0x8694308)
    at /build/buildd/kdepim-3.5.5/./kmail/urlhandlermanager.cpp:312
#10 0xb7c407a9 in KMReaderWin::slotUrlOn (this=0x8694308, aUrl=@0x8b125c8)
    at /build/buildd/kdepim-3.5.5/./kmail/kmreaderwin.cpp:1855
#11 0xb7c40bf6 in KMReaderWin::qt_invoke (this=0x8694308, _id=58, 
    _o=0xbffc46b8) at ./kmreaderwin.moc:292
#12 0xb7066787 in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#13 0xb7066cbc in QObject::activate_signal () from /usr/lib/libqt-mt.so.3
#14 0xb6a79180 in KHTMLPart::onURL (this=0x869ad88, t0=@0x86f7bc0)
    at ./khtml_part.moc:409
#15 0xb6a81bed in KHTMLPart::overURL (this=0x869ad88, url=@0x86f7bc0, 
    target=@0xbffc4fe8)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./khtml/khtml_part.cpp:3720
#16 0xb6a9a80e in KHTMLPart::khtmlMouseMoveEvent (this=0x869ad88, 
    event=0xbffc534c)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./khtml/khtml_part.cpp:6475
#17 0xb6a65020 in KHTMLPart::customEvent (this=0x869ad88, event=0xbffc534c)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./khtml/khtml_part.cpp:5947
#18 0xb7065e89 in QObject::event () from /usr/lib/libqt-mt.so.3
#19 0xb6ffd9a8 in QApplication::internalNotify () from /usr/lib/libqt-mt.so.3
#20 0xb6fff7d7 in QApplication::notify () from /usr/lib/libqt-mt.so.3
#21 0xb77228c2 in KApplication::notify (this=0xbffc6094, receiver=0x869ad88, 
    event=0xbffc534c)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kdecore/kapplication.cpp:550
#22 0xb6aa5632 in KHTMLView::viewportMouseMoveEvent (this=0x86d6f30, 
    _mouse=0xbffc5a40) at /usr/share/qt3/include/qapplication.h:520
#23 0xb719d412 in QScrollView::eventFilter () from /usr/lib/libqt-mt.so.3
#24 0xb6a6d439 in KHTMLView::eventFilter (this=0x86d6f30, o=0x86fb150, 
    e=0xbffc5a40)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./khtml/khtmlview.cpp:1939
#25 0xb7065d34 in QObject::activate_filters () from /usr/lib/libqt-mt.so.3
#26 0xb7065db2 in QObject::event () from /usr/lib/libqt-mt.so.3
#27 0xb709d48b in QWidget::event () from /usr/lib/libqt-mt.so.3
#28 0xb6ffd9a8 in QApplication::internalNotify () from /usr/lib/libqt-mt.so.3
#29 0xb6fffb66 in QApplication::notify () from /usr/lib/libqt-mt.so.3
#30 0xb77228c2 in KApplication::notify (this=0xbffc6094, receiver=0x86fb150, 
    event=0xbffc5a40)
    at /build/buildd/kdelibs-3.5.5a.dfsg.1/./kdecore/kapplication.cpp:550
#31 0xb6f9021d in QApplication::sendSpontaneousEvent ()
   from /usr/lib/libqt-mt.so.3
#32 0xb6f8ee82 in QETWidget::translateMouseEvent ()
   from /usr/lib/libqt-mt.so.3
#33 0xb6f8cf6c in QApplication::x11ProcessEvent () from /usr/lib/libqt-mt.so.3
#34 0xb6fa4140 in QEventLoop::processEvents () from /usr/lib/libqt-mt.so.3
#35 0xb701807e in QEventLoop::enterLoop () from /usr/lib/libqt-mt.so.3
#36 0xb7017e8e in QEventLoop::exec () from /usr/lib/libqt-mt.so.3
#37 0xb6fff551 in QApplication::exec () from /usr/lib/libqt-mt.so.3
#38 0x0804a2de in main (argc=)
    at /build/buildd/kdepim-3.5.5/./kmail/main.cpp:110
#39 0xb77c0ebc in __libc_start_main () from /lib/libc.so.6
#40 0x0804a041 in _start ()