Version:           1.11.4 (using KDE 4.2.4)
Compiler:          gcc (Gentoo 4.3.3-r2 p1.2, pie-10.1.5) 4.3.3
 
OS:                Linux
Installed from:    Gentoo Packages

When I make a search through all folders (~30000 mails), KMail crashes after some seconds with following backtrace :

Application : Kontact (kontact), signal SIGABRT

Thread 1 (Thread 0xb7f0e920 (LWP 3699)):
[KCrash Handler]
#6  0xb7f4c424 in __kernel_vsyscall ()
#7  0x4f394980 in raise (sig=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#8  0x4f3961c8 in abort () at abort.c:88
#9  0x414a5910 in __gnu_cxx::__verbose_terminate_handler () at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/vterminate.cc:98
#10 0x414a37f6 in __cxxabiv1::__terminate (handler=<value optimized out>) at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/eh_terminate.cc:43
#11 0x414a3833 in std::terminate () at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/eh_terminate.cc:53
#12 0x414a396b in __cxa_throw (obj=) at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/eh_throw.cc:76
#13 0x414a3fdb in operator new (sz=<value optimized out>) at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/new_op.cc:63
#14 0x414a40be in operator new[] (sz=<value optimized out>) at /var/tmp/portage/sys-devel/gcc-4.3.3-r2/work/gcc-4.3.3/libstdc++-v3/libsupc++/new_opv.cc:37
#15 0x4484a69e in KMFolderMbox::getDwString (this=<value optimized out>, idx=) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4/kmail/kmfoldermbox.cpp:980
#16 0x4476e193 in KMFolder::getDwString (this=) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4/kmail/kmfolder.cpp:382
#17 0x447f1ac1 in KMSearchPattern::matches (this=0x9b8f528, serNum=173419901, ignoreBody=148) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4/kmail/kmsearchpattern.cpp:797
#18 0x447a1be0 in FolderStorage::slotProcessNextSearchBatch (this=) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4/kmail/folderstorage.cpp:1170
#19 0x447a1d77 in FolderStorage::qt_metacall (this=) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4_build/kmail/folderstorage.moc:146
#20 0x449ae003 in KMFolderIndex::qt_metacall (this=<value optimized out>, _c=<value optimized out>, _id=<value optimized out>, _a=)
    at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4_build/kmail/kmfolderindex.moc:63
#21 0x44848924 in KMFolderMbox::qt_metacall (this=) at /var/tmp/portage/kde-base/kmail-4.2.4/work/kmail-4.2.4_build/kmail/kmfoldermbox.moc:58
#22 0x4114ad59 in QMetaObject::activate (sender=) at kernel/qobject.cpp:3101
#23 0x4114b386 in QMetaObject::activate (sender=<value optimized out>, m=) at kernel/qobject.cpp:3178
#24 0x41151a46 in QSingleShotTimer::timeout (this=0xa46f790) at .moc/release-shared/qtimer.moc:76
#25 0x41151b8d in QSingleShotTimer::timerEvent (this=0xa46f790) at kernel/qtimer.cpp:298
#26 0x4114790b in QObject::event (this=) at kernel/qobject.cpp:1066
#27 0x42bf52f4 in QApplicationPrivate::notify_helper (this=<value optimized out>, receiver=<value optimized out>, e=<value optimized out>) at kernel/qapplication.cpp:4056
#28 0x42bfe1ab in QApplication::notify (this=) at kernel/qapplication.cpp:3603
#29 0x4379e6f2 in KApplication::notify (this=<value optimized out>, receiver=) at /var/tmp/portage/kde-base/kdelibs-4.2.4-r3/work/kdelibs-4.2.4/kdeui/kernel/kapplication.cpp:307
#30 0x41137bfd in QCoreApplication::notifyInternal (this=) at kernel/qcoreapplication.cpp:606
#31 0x41163f46 in QTimerInfoList::activateTimers (this=<value optimized out>) at kernel/qcoreapplication.h:213
#32 0x41160bff in timerSourceDispatch (source=) at kernel/qeventdispatcher_glib.cpp:165
#33 0x4212a8fb in IA__g_main_context_dispatch (context=0x90ef2f0) at gmain.c:1824
#34 0x4212e068 in g_main_context_iterate (context=0x90ef2f0, block=1, dispatch=1, self=0x90edf30) at gmain.c:2455
#35 0x4212e1f0 in IA__g_main_context_iteration (context=0x90ef2f0, may_block=1) at gmain.c:2518
#36 0x41160b59 in QEventDispatcherGlib::processEvents (this=) at kernel/qeventdispatcher_glib.cpp:327
#37 0x42c8a96b in QGuiEventDispatcherGlib::processEvents (this=) at kernel/qguieventdispatcher_glib.cpp:202
#38 0x411362b4 in QEventLoop::processEvents (this=) at kernel/qeventloop.cpp:149
#39 0x4113648d in QEventLoop::exec (this=) at kernel/qeventloop.cpp:197
#40 0x41138782 in QCoreApplication::exec () at kernel/qcoreapplication.cpp:888
#41 0x42bf5145 in QApplication::exec () at kernel/qapplication.cpp:3525
#42 0x0804c28a in main (argc=-1077625884, argv=0xbfc4b920) at /var/tmp/portage/kde-base/kontact-4.2.4/work/kontact-4.2.4/kontact/src/main.cpp:218

and it seems to consume lots of memory.