[kde-linux] Desktop hangs, kwallet crashes

[aladdin]

I am running Debian Linux 2.6 and just upgraded my system (including KDE),
so its now version 4.2.  Ever since I did this, KDE has been quite flaky.  The
problems listed in the subject, where the window dressings go away and you
can no long restore or start programs from the task bar (although the individual
programs respond find to their menus if they happen to be visible), requiring
one to log off and back on which fixes everything.  Also, when you log off,
kwallet crashes.  On three occasions (over the past week or so), the desktop
has just gone away altogether, popping up logon splash screen, and on two
occasions the system has spontaneously rebooted (I realize this last can't be
directly attributed to KDE without further debugging, but it suspiciously
started happening at exactly the same time as the KDE problems).

Is there a log somewhere that might have germane data in it?

TIA,
allen