Application that crashed: kmail
Version of the application: 1.11.90
KDE Version: 4.2.87 (KDE 4.2.87 (KDE 4.3 >= 20090519))
Qt Version: 4.5.1
Operating System: Linux 2.6.28.5 x86_64

What I was doing when the application crashed:
Kmail working like normal, did not get the crash dialog until exiting kmail.  I closed kmail via the x in the upper right hand corner, I was unfortunatly unable to duplicate, I reopened and closed kmail a couple more times with out issue. 

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#5  0x00007f37f98718a0 in QListData::shared_null () from /opt/qt-4.5/lib/libQtCore.so.4
#6  0x00007f37f9ec7902 in qDeleteAll<QList<KIO::Slave*>::const_iterator> () from /opt/lib/libkio.so.5
#7  0x00007f37f9ec83a6 in qDeleteAll<QHash<QString, KIO::SchedulerPrivate::ProtocolInfo*>::const_iterator> () from /opt/lib/libkio.so.5
#8  0x00007f37f9ec4419 in ._257::destroy () from /opt/lib/libkio.so.5
#9  0x00007f37f7747f80 in exit () from /lib64/libc.so.6
#10 0x00007f37f773116b in __libc_start_main () from /lib64/libc.so.6
#11 0x00000000004023c9 in _start ()

This bug may be a duplicate of or related to bug 192858