Version:            (using KDE 4.0.83)
Installed from:    Debian testing/unstable Packages

when sending a message and the main window is hidden kmail crashes:

Application: KMail (kmail), signal SIGSEGV
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 0x7f6df9d1b780 (LWP 5396)]
[KCrash handler]
#5  QFactoryLoader::keys (this=0x0) at plugin/qfactoryloader_p.h:71
#6  0x00007f6df78235f5 in createWriteHandlerHelper (device=0x7fff01e66cb0, 
    format=@0x1009620) at image/qimagewriter.cpp:137
#7  0x00007f6df782558c in QImageWriter::canWrite (this=0x7fff01e66c10)
    at image/qimagewriter.cpp:547
#8  0x00007f6df7825633 in QImageWriter::write (this=0x7fff01e66ab0, 
    image=@0x0) at image/qimagewriter.cpp:567
#9  0x00007f6df780eb96 in QImage::save (this=0x7fff01e66c50, 
    device=0x7fff01e66cb0, format=<value optimized out>, quality=-1)
    at image/qimage.cpp:4591
#10 0x00007f6df5cdf849 in KABC::VCardTool::createPicture (
    this=<value optimized out>, identifier=<value optimized out>, 
    pic=@0x7fff01e67cb0)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/vcardtool.cpp:712
#11 0x00007f6df5ce2565 in KABC::VCardTool::createVCards (this=0x7fff01e685f0, 
    list=<value optimized out>, version=KABC::VCard::v3_0)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/vcardtool.cpp:254
#12 0x00007f6df5cd3ef0 in KABC::VCardConverter::createVCards (
    this=<value optimized out>, list=
        {<QList<KABC::Addressee>> = {{p = {static shared_null = {ref = {_q_value = 2314}, alloc = 0, begin = 0, end = 0, sharable = 1, array = {0x0}}, d = 0x7fff01e68650}, d = 0x7fff01e68650}}, d = {d = 0x7fff01e686a0}}, 
    version=KABC::VCardConverter::v3_0)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/vcardconverter.cpp:47
#13 0x00007f6df5cd4cbb in KABC::VCardFormat::saveAll (
    this=<value optimized out>, resource=0x1843e10, file=0x7fff01e68720)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/vcardformat.cpp:101
#14 0x00007f6de2316529 in KABC::ResourceFile::saveToFile (this=0x1843e10, 
    file=0x7fff01e68720)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/plugins/file/resourcefile.cpp:377
#15 0x00007f6de23168d3 in KABC::ResourceFile::save (this=0x1843e10, 
    ticket=<value optimized out>)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/plugins/file/resourcefile.cpp:260
#16 0x00007f6df5ca274a in KABC::AddressBook::save (
    this=<value optimized out>, ticket=0x195def0)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/addressbook.cpp:383
#17 0x00007f6df5cd2ec5 in KABC::StdAddressBook::Private::saveAll (
    this=0x183f4a0)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/stdaddressbook.cpp:173
#18 0x00007f6df5cd3119 in ~StdAddressBook (this=0x182fc10)
    at /tmp/buildd/kdepimlibs-4.0.82+svn819867/kabc/stdaddressbook.cpp:109
#19 0x00007f6df5cd3d5f in ~K3StaticDeleter (this=0x7f6df5f09160)
    at /usr/include/k3staticdeleter.h:174
#20 0x00007f6df6d69d68 in __cxa_finalize () from /lib/libc.so.6
#21 0x00007f6df5c9acf6 in __do_global_dtors_aux () from /usr/lib/libkabc.so.4
#22 0x00000000023318e0 in ?? ()
#23 0x00007fff01e68ec0 in ?? ()
#24 0x00007f6df5cf5bd1 in _fini () from /usr/lib/libkabc.so.4
#25 0x0000000000000093 in ?? ()
#26 0x00007f6df9c5ce04 in _dl_fini () from /lib64/ld-linux-x86-64.so.2
Backtrace stopped: previous frame inner to this frame (corrupt stack?)
#0  0x00007f6df6dd31f1 in nanosleep () from /lib/libc.so.6