Version:           r822278 (using Devel)
Installed from:    Compiled sources
Compiler:          4.1.2 
OS:                Linux

if you make an empty bookmark folder an then try to "open folder in tabs", konqueror crashes, perhaps this option could be disabled.

backtrace: 

#5  0x00002af3367d5a4d in QUrl::scheme (this=0xa6e382) at io/qurl.cpp:4004
#6  0x00002af3334daec6 in KUrl::prettyUrl (this=0xa6e382,
    trailing=KUrl::LeaveTrailingSlash)
    at /var/tmp/portage/kde-base/kdelibs-9999/work/kdelibs-9999/kdecore/io/kurl.cpp:979
#7  0x00002af3334d2551 in operator<< (s=@0x7fff7868fd20, url=@0xa6e382)
    at /var/tmp/portage/kde-base/kdelibs-9999/work/kdelibs-9999/kdecore/io/kdebug.cpp:626
#8  0x00002af3326ae0fd in KonqMainWindow::openUrl (this=0x7477b0, _view=0x0,
    _url=@0xa6e382, _mimeType=@0x7fff78690070, req=@0x7fff7868ffe0,
    trustedSource=false)
    at /var/tmp/portage/kde-base/konqueror-9999/work/konqueror/apps/konqueror/src/konqmainwindow.cpp:503
#9  0x00002af3326af034 in KonqExtendedBookmarkOwner::openFolderinTabs (
    this=0x7c1330, grp=<value optimized out>)
    at /var/tmp/portage/kde-base/konqueror-9999/work/konqueror/apps/konqueror/src/konqmainwindow.cpp:4408
#10 0x00002af33310add8 in KBookmarkMenu::slotOpenFolderInTabs (this=0x852e50)
    at /var/tmp/portage/kde-base/kdelibs-9999/work/kdelibs-9999/kio/bookmarks/kbookmarkmenu.cc:586
#11 0x00002af33310d2ca in KBookmarkMenu::qt_metacall (this=0x852e50,
    _c=QMetaObject::InvokeMetaMethod, _id=5, _a=0x7fff78690250)
    at /var/tmp/portage/kde-base/kdelibs-9999/work/kdelibs_build/kio/kbookmarkmenu.moc:80
#12 0x00002af33682dbaa in QMetaObject::activate (sender=0x115ad50,
    from_signal_index=<value optimized out>, to_signal_index=6, argv=0xd121b0)
    at kernel/qobject.cpp:3001
#13 0x00002af33736629b in QAction::triggered (this=0x0, _t1=false)
    at .moc/debug-shared/moc_qaction.cpp:216
....