[imp] User can't log in

[Roger B.A. Klorese]

After closing his browser abruptly, one of my users gets the following
when he attempts to log in:

  Warning: unserialize() failed at offset 0 of 33 bytes in
/var/www/html/horde/lib/Auth.php on line 249

  Warning: Cannot add header information - headers already sent by
(output started at   
  /var/www/html/horde/lib/Auth.php:249) in
/var/www/html/horde/imp/index.php on line 28

We have since rebooted the server, cleared the cached files on the
browser...

This is HEAD, checked out July 22, 2002.  Yes, a bit long in the tooth,
but we're using groups in Turba, and I haven't figured out how tp update
easily.