Version:           1.8.50 (using KDE 3.4.89 (>= 20050615), compiled sources)
Compiler:          gcc version 3.4.4 20050314 (prerelease) (Debian 3.4.3-12)
OS:                Linux (i686) release 2.6.11.7

go to settings, identities, cryptography, try to  choose your encryption key. Kaboom:
Using host libthread_db library "/lib/tls/libthread_db.so.1".
`system-supplied DSO at 0xffffe000' has disappeared; keeping its symbols.
[Thread debugging using libthread_db enabled]
[New Thread -1243511104 (LWP 14201)]
[KCrash handler]
#3  0xb53f0fd8 in __gnu_cxx::__mt_alloc<GpgME::UserID>::deallocate (
    this=0xbfffe060, __p=0x9502658, __n=0) at mt_allocator.h:430
#4  0xb53f02cf in KMail::(anonymous namespace)::DoesntMatchEMailAddress::operator() (this=0xbfffe250, key=@0x9a332d8) at stl_vector.h:117
#5  0xb53f1244 in std::find_if<__gnu_cxx::__normal_iterator<GpgME::Key const*, std::vector<GpgME::Key, std::allocator<GpgME::Key> > >, KMail::(anonymous namespace)::DoesntMatchEMailAddress> (__first={_M_current = 0x9a332d8}, __pred=
        {email = {static null = {static null = <same as static member of an already seen type>, d = 0x8070070, static shared_null = 0x8070070}, d = 0x84fbc28, static shared_null = 0x8070070}}) at stl_iterator.h:614
#6  0xb53f06a6 in KMail::IdentityDialog::slotOk (this=0x9f46e50)
    at /home/gj/kde-sources/kdepim/kmail/identitydialog.cpp:479
#7  0xb70baa4b in KDialogBase::qt_invoke (this=0x9f46e50, _id=73, 
    _o=0xbfffe3a0) at kdialogbase.moc:359
#8  0xb53eafb3 in KMail::IdentityDialog::qt_invoke (this=0x9f46e50, _id=73, 
    _o=0x9f46e50) at identitydialog.moc:96
#9  0xb66f1e7b in QObject::activate_signal (this=0x9fd2178, clist=0x9e6bfd8, 
    o=0xbfffe3a0) at kernel/qobject.cpp:2355
#10 0xb66f1d1d in QObject::activate_signal (this=0x9fd2178, signal=4)
    at kernel/qobject.cpp:2324
#11 0xb6a5f96b in QButton::clicked (this=0x9fd2178)
    at .moc/debug-shared-mt/moc_qbutton.cpp:152
#12 0xb678a393 in QButton::mouseReleaseEvent (this=0x9fd2178, e=0xbfffe7d0)
    at widgets/qbutton.cpp:836
#13 0xb672b9df in QWidget::event (this=0x9fd2178, e=0xbfffe7d0)
    at kernel/qwidget.cpp:4676
#14 0xb668d4fd in QApplication::internalNotify (this=0xbffff830, 
    receiver=0x9fd2178, e=0xbfffe7d0) at kernel/qapplication.cpp:2635
#15 0xb668ccb8 in QApplication::notify (this=0xbffff830, receiver=0x9fd2178, 
    e=0xbfffe7d0) at kernel/qapplication.cpp:2421
#16 0xb6d160a3 in KApplication::notify (this=0xbffff830, receiver=0x9fd2178, 
    event=0xbfffe7d0)
    at /home/gj/kde-sources/kdelibs/kdecore/kapplication.cpp:549
#17 0xb661e641 in QApplication::sendSpontaneousEvent (receiver=0x9fd2178, 
    event=0xbfffe7d0) at qapplication.h:494
#18 0xb6618c0b in QETWidget::translateMouseEvent (this=0x9fd2178, 
    event=0xbfffeb70) at kernel/qapplication_x11.cpp:4304
#19 0xb6616854 in QApplication::x11ProcessEvent (this=0xbffff830, 
    event=0xbfffeb70) at kernel/qapplication_x11.cpp:3455
#20 0xb6631b29 in QEventLoop::processEvents (this=0x80a4e78, flags=4)
    at kernel/qeventloop_x11.cpp:192
#21 0xb66a2588 in QEventLoop::enterLoop (this=0x80a4e78)
    at kernel/qeventloop.cpp:198
#22 0xb668d6e7 in QApplication::enter_loop (this=0xbffff830)
    at kernel/qapplication.cpp:2790
#23 0xb6891fbd in QDialog::exec (this=0x9f46e50) at dialogs/qdialog.cpp:432
#24 0xb539fd97 in IdentityPage::slotModifyIdentity (this=0x9105f58)
    at /home/gj/kde-sources/kdepim/kmail/configuredialog.cpp:416
#25 0xb53d29bc in IdentityPage::qt_invoke (this=0x9105f58, _id=152067928, 
    _o=0xbfffed40) at configuredialog_p.moc:728
#26 0xb66f1e7b in QObject::activate_signal (this=0x985c9c8, clist=0x9c0b0e0, 
    o=0xbfffed40) at kernel/qobject.cpp:2355
#27 0xb6a6ea27 in QListView::doubleClicked (this=0x985c9c8, t0=0x9438450, 
    t1=@0xbfffee44, t2=1) at .moc/debug-shared-mt/moc_qlistview.cpp:412
#28 0xb7053376 in KListView::doubleClicked (this=0x985c9c8, item=0x9438450, 
    pos=@0xbfffee44, c=1)
    at /home/gj/kde-sources/kdelibs/kdeui/klistview.cpp:2126
#29 0xb7056a3f in KListView::contentsMouseDoubleClickEvent (this=0x985c9c8, 
    e=0xbfffee30) at qevent.h:181
#30 0xb681bccb in QScrollView::viewportMouseDoubleClickEvent (this=0x985c9c8, 
    e=0xbffff380) at widgets/qscrollview.cpp:1768
#31 0xb681b2d4 in QScrollView::eventFilter (this=0x985c9c8, obj=0x8b58278, 
    e=0xbffff380) at widgets/qscrollview.cpp:1507
#32 0xb67e456b in QListView::eventFilter (this=0x985c9c8, o=0x8b58278, 
    e=0xbffff380) at widgets/qlistview.cpp:3841
#33 0xb66ef908 in QObject::activate_filters (this=0x8b58278, e=0xbffff380)
    at kernel/qobject.cpp:902
#34 0xb66ef77c in QObject::event (this=0x8b58278, e=0xbffff380)
    at kernel/qobject.cpp:735
#35 0xb672b903 in QWidget::event (this=0x8b58278, e=0xbffff380)
    at kernel/qwidget.cpp:4658
#36 0xb668d4fd in QApplication::internalNotify (this=0xbffff830, 
    receiver=0x8b58278, e=0xbffff380) at kernel/qapplication.cpp:2635
#37 0xb668ccb8 in QApplication::notify (this=0xbffff830, receiver=0x8b58278, 
    e=0xbffff380) at kernel/qapplication.cpp:2421
#38 0xb6d160a3 in KApplication::notify (this=0xbffff830, receiver=0x8b58278, 
    event=0xbffff380)
    at /home/gj/kde-sources/kdelibs/kdecore/kapplication.cpp:549
#39 0xb661e641 in QApplication::sendSpontaneousEvent (receiver=0x8b58278, 
    event=0xbffff380) at qapplication.h:494
#40 0xb6618c0b in QETWidget::translateMouseEvent (this=0x8b58278, 
    event=0xbffff720) at kernel/qapplication_x11.cpp:4304
#41 0xb6616854 in QApplication::x11ProcessEvent (this=0xbffff830, 
    event=0xbffff720) at kernel/qapplication_x11.cpp:3455
#42 0xb6631b29 in QEventLoop::processEvents (this=0x80a4e78, flags=4)
    at kernel/qeventloop_x11.cpp:192
#43 0xb66a2588 in QEventLoop::enterLoop (this=0x80a4e78)
    at kernel/qeventloop.cpp:198
#44 0xb66a24a6 in QEventLoop::exec (this=0x80a4e78)
    at kernel/qeventloop.cpp:145
#45 0xb668d67d in QApplication::exec (this=0xbffff830)
    at kernel/qapplication.cpp:2758
#46 0x08059591 in main (argc=1, argv=0xbffffab4)
    at /home/gj/kde-sources/kdepim/kontact/src/main.cpp:177