Application that crashed: kmail
Version of the application: 1.12.1
KDE Version: 4.3.1 (KDE 4.3.1)
Qt Version: 4.5.2
Operating System: Linux 2.6.30-ARCH i686

What I was doing when the application crashed:
Opened a new composition window in Kmail, started to type the first few characters if the To field and Kmail crashed completely after the second or third character.  Kmail was setup to lookup addresses in company ldap address book.
This worked fine in KDE 4.3.0.  This bug occurs regulary since upgrading to KDE 4.3.1. System is Arch Linux with KDEmod.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#6  0xb7124bcf in KPIM::AddresseeLineEdit::slotLDAPSearchData () from /usr/lib/libkdepim.so.4
#7  0xb7124e45 in KPIM::AddresseeLineEdit::qt_metacall () from /usr/lib/libkdepim.so.4
#8  0xb75bcb9a in KMLineEdit::qt_metacall () from /usr/lib/libkmailprivate.so.4
#9  0xb763379a in RecipientLineEdit::qt_metacall () from /usr/lib/libkmailprivate.so.4
#10 0xb6fbb9ac in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#11 0xb6fbc5e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#12 0xb7127e93 in KPIM::LdapSearch::searchData () from /usr/lib/libkdepim.so.4
#13 0xb712becf in KPIM::LdapSearch::slotDataTimer () from /usr/lib/libkdepim.so.4
#14 0xb712bf5d in KPIM::LdapSearch::finish () from /usr/lib/libkdepim.so.4
#15 0xb712bfa0 in KPIM::LdapSearch::slotLDAPDone () from /usr/lib/libkdepim.so.4
#16 0xb712ea03 in KPIM::LdapSearch::qt_metacall () from /usr/lib/libkdepim.so.4
#17 0xb6fbb9ac in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#18 0xb6fbc5e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#19 0xb7127fc7 in KPIM::LdapClient::done () from /usr/lib/libkdepim.so.4
#20 0xb712875f in KPIM::LdapClient::slotDone () from /usr/lib/libkdepim.so.4
#21 0xb712c4c3 in KPIM::LdapClient::qt_metacall () from /usr/lib/libkdepim.so.4
#22 0xb6fbb9ac in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#23 0xb6fbc5e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#24 0xb7a41ab3 in KJob::result () from /usr/lib/libkdecore.so.5
#25 0xb7a41f39 in KJob::emitResult () from /usr/lib/libkdecore.so.5
#26 0xb51de2e0 in KIO::SimpleJob::slotFinished () from /usr/lib/libkio.so.5
#27 0xb51de7fa in KIO::TransferJob::slotFinished () from /usr/lib/libkio.so.5
#28 0xb51dc523 in KIO::TransferJob::qt_metacall () from /usr/lib/libkio.so.5
#29 0xb6fbb9ac in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#30 0xb6fbc5e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#31 0xb52a7727 in KIO::SlaveInterface::finished () from /usr/lib/libkio.so.5
#32 0xb52ab61d in KIO::SlaveInterface::dispatch () from /usr/lib/libkio.so.5
#33 0xb52a7be3 in KIO::SlaveInterface::dispatch () from /usr/lib/libkio.so.5
#34 0xb5299cda in KIO::Slave::gotInput () from /usr/lib/libkio.so.5
#35 0xb529c0d3 in KIO::Slave::qt_metacall () from /usr/lib/libkio.so.5
#36 0xb6fbb9ac in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#37 0xb6fbc5e2 in QMetaObject::activate () from /usr/lib/libQtCore.so.4
#38 0xb51a4cc7 in KIO::Connection::readyRead () from /usr/lib/libkio.so.5
#39 0xb51a6a7e in KIO::ConnectionPrivate::dequeue () from /usr/lib/libkio.so.5
#40 0xb51a6bae in KIO::Connection::qt_metacall () from /usr/lib/libkio.so.5
#41 0xb6fb469b in QMetaCallEvent::placeMetaCall () from /usr/lib/libQtCore.so.4
#42 0xb6fb5d9e in QObject::event () from /usr/lib/libQtCore.so.4
#43 0xb65f7964 in QApplicationPrivate::notify_helper () from /usr/lib/libQtGui.so.4
#44 0xb65ff04c in QApplication::notify () from /usr/lib/libQtGui.so.4
#45 0xb7db446a in KApplication::notify () from /usr/lib/libkdeui.so.5
#46 0xb6fa5fcb in QCoreApplication::notifyInternal () from /usr/lib/libQtCore.so.4
#47 0xb6fa6bb2 in QCoreApplicationPrivate::sendPostedEvents () from /usr/lib/libQtCore.so.4
#48 0xb6fa6d7d in QCoreApplication::sendPostedEvents () from /usr/lib/libQtCore.so.4
#49 0xb6fd0a9f in ?? () from /usr/lib/libQtCore.so.4
#50 0xb4663d98 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#51 0xb46673e0 in g_main_context_iterate () from /usr/lib/libglib-2.0.so.0
#52 0xb4667513 in g_main_context_iteration () from /usr/lib/libglib-2.0.so.0
#53 0xb6fd06cc in QEventDispatcherGlib::processEvents () from /usr/lib/libQtCore.so.4
#54 0xb6695695 in ?? () from /usr/lib/libQtGui.so.4
#55 0xb6fa4579 in QEventLoop::processEvents () from /usr/lib/libQtCore.so.4
#56 0xb6fa49ca in QEventLoop::exec () from /usr/lib/libQtCore.so.4
#57 0xb6fa6e3f in QCoreApplication::exec () from /usr/lib/libQtCore.so.4
#58 0xb65f77e7 in QApplication::exec () from /usr/lib/libQtGui.so.4
#59 0x0804a6b2 in _start ()

Reported using DrKonqi