Application that crashed: kmail
Version of the application: 1.11.90
KDE Version: 4.2.90 (KDE 4.2.90 (KDE 4.3 Beta2))
Qt Version: 4.5.0
Operating System: Linux 2.6.28-11-generic i686
Distribution: Ubuntu 9.04

What I was doing when the application crashed:
When I start kmail it asks for a password of one of my imap accounts configured in kmail. When I enter the passwort or when I hit cancel kmail always crashes with the following bt.

 -- Backtrace:
Application: KMail (kmail), signal: Segmentation fault
[KCrash Handler]
#6  QTreeWidget::setItemExpanded (this=0x19, item=0x92cde48, expand=false) at itemviews/qtreewidget.h:370
#7  0xb738605c in KMail::FolderView::slotFolderExpanded (this=0x92b0e70, item=0x92cde48) at /usr/include/qt4/QtGui/qtreewidget.h:409
#8  0xb73919f5 in KMail::FolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=30, _a=0xbfbfdb4c) at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/folderview.moc:226
#9  0xb73951fa in KMail::MainFolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=157, _a=0xbfbfdb4c)
    at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/mainfolderview.moc:64
#10 0xb5f6fca8 in QMetaObject::activate (sender=0x92b0e70, from_signal_index=101, to_signal_index=101, argv=0xbfbfdb4c) at kernel/qobject.cpp:3069
#11 0xb5f70932 in QMetaObject::activate (sender=0x92b0e70, m=0xb6aa0ad0, local_signal_index=6, argv=0xbfbfdb4c) at kernel/qobject.cpp:3143
#12 0xb67f7d23 in QTreeWidget::itemExpanded (this=0x92b0e70, _t1=0x92cde48) at .moc/release-shared/moc_qtreewidget.cpp:236
#13 0xb67fd056 in QTreeWidgetPrivate::_q_emitItemExpanded (this=0x932d8a0, index=@0xbfbfdddc) at itemviews/qtreewidget.cpp:2258
#14 0xb680540f in QTreeWidget::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=21, _a=0xbfbfdd2c) at .moc/release-shared/moc_qtreewidget.cpp:149
#15 0xb71a32ca in KPIM::TreeWidget::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=116, _a=0xbfbfdd2c)
    at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/libkdepim/moc_treewidget.cpp:68
#16 0xb7206dfa in KPIM::FolderTreeWidget::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=116, _a=0xbfbfdd2c)
    at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/libkdepim/foldertreewidget.moc:68
#17 0xb739199a in KMail::FolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=116, _a=0xbfbfdd2c) at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/folderview.moc:191
#18 0xb73951fa in KMail::MainFolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=116, _a=0xbfbfdd2c)
    at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/mainfolderview.moc:64
#19 0xb5f6fca8 in QMetaObject::activate (sender=0x92b0e70, from_signal_index=69, to_signal_index=69, argv=0xbfbfdd2c) at kernel/qobject.cpp:3069
#20 0xb5f70932 in QMetaObject::activate (sender=0x92b0e70, m=0xb6aa0190, local_signal_index=0, argv=0xbfbfdd2c) at kernel/qobject.cpp:3143
#21 0xb67b9103 in QTreeView::expanded (this=0x92b0e70, _t1=@0xbfbfdddc) at .moc/release-shared/moc_qtreeview.cpp:213
#22 0xb67ca9fe in QTreeView::expand (this=0x92b0e70, index=@0xbfbfdddc) at itemviews/qtreeview.cpp:752
#23 0xb67cb52c in QTreeView::setExpanded (this=0x19, index=@0x0, expanded=true) at itemviews/qtreeview.cpp:825
#24 0xb680063c in QTreeWidget::setItemExpanded (this=0x92b0e70, item=0x92cde48, expand=true) at itemviews/qtreewidget.cpp:3114
#25 0xb738a88c in KMail::FolderView::restoreItemStates (this=0x92b0e70) at /usr/include/qt4/QtGui/qtreewidget.h:409
#26 0xb73916bd in KMail::FolderView::reload (this=0x92b0e70, openFoldersForUpdate=false) at /build/buildd/kdepim-4.2.90/kmail/folderview.cpp:762
#27 0xb7391936 in KMail::FolderView::slotColumnVisibilityChanged (this=0x92b0e70, logicalIndex=3) at /build/buildd/kdepim-4.2.90/kmail/folderview.cpp:600
#28 0xb7391b41 in KMail::FolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=14, _a=0xbfbfe0cc) at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/folderview.moc:210
#29 0xb73951fa in KMail::MainFolderView::qt_metacall (this=0x92b0e70, _c=QMetaObject::InvokeMetaMethod, _id=141, _a=0xbfbfe0cc)
    at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/kmail/mainfolderview.moc:64
#30 0xb5f6fca8 in QMetaObject::activate (sender=0x92b0e70, from_signal_index=122, to_signal_index=122, argv=0xbfbfe0cc) at kernel/qobject.cpp:3069
#31 0xb5f70932 in QMetaObject::activate (sender=0x92b0e70, m=0xb725d660, local_signal_index=0, argv=0xbfbfe0cc) at kernel/qobject.cpp:3143
#32 0xb71a2fb3 in KPIM::TreeWidget::columnVisibilityChanged (this=0x92b0e70, _t1=3) at /build/buildd/kdepim-4.2.90/obj-i486-linux-gnu/libkdepim/moc_treewidget.cpp:87
#33 0xb7203fdd in KPIM::TreeWidget::setColumnHidden (this=0x92b0e70, logicalIndex=3, hide=<value optimized out>) at /build/buildd/kdepim-4.2.90/libkdepim/treewidget.cpp:204
#34 0xb7389803 in KMail::FolderView::readConfig (this=0x92b0e70) at /build/buildd/kdepim-4.2.90/kmail/folderview.cpp:274
#35 0xb75fb520 in KMMainWidget::readConfig (this=0x9245c90) at /build/buildd/kdepim-4.2.90/kmail/kmmainwidget.cpp:594
#36 0xb760f600 in KMMainWidget (this=0x9245c90, parent=0x92375e0, aGUIClient=0x9237614, actionCollection=0x9245a38, config=0x8ea9958) at /build/buildd/kdepim-4.2.90/kmail/kmmainwidget.cpp:233
#37 0xb7310bbb in KMMainWin (this=0x92375e0) at /build/buildd/kdepim-4.2.90/kmail/kmmainwin.cpp:41
#38 0xb7522721 in KMKernel::openReader (this=0xbfbfe6a8, onlyCheck=false) at /build/buildd/kdepim-4.2.90/kmail/kmkernel.cpp:391
#39 0xb7523924 in KMKernel::action (this=0xbfbfe6a8, mailto=false, check=<value optimized out>, to=@0xbfbfe628, cc=@0xbfbfe624, bcc=@0xbfbfe620, subj=@0xbfbfe61c, body=@0xbfbfe618, 
    messageFile=@0xbfbfe564, attachURLs=@0xbfbfe610, customHeaders=@0xbfbfe614) at /build/buildd/kdepim-4.2.90/kmail/kmkernel.cpp:1848
#40 0xb7524ccb in KMKernel::handleCommandLine (this=0xbfbfe6a8, noArgsOpensReader=true) at /build/buildd/kdepim-4.2.90/kmail/kmkernel.cpp:337
#41 0x0804af9d in KMailApplication::newInstance (this=0xbfbfe758) at /build/buildd/kdepim-4.2.90/kmail/main.cpp:84
#42 0x0804a7ab in main (argc=) at /build/buildd/kdepim-4.2.90/kmail/main.cpp:143

Reported using DrKonqi