The remote host is missing an update as announced via advisory SSA:2005-255-01.
New util-linux packages are available for Slackware 8.1, 9.0, 9.1, 10.0, 10.1, and -current to fix a security issue with umount. A bug in the '-r' option could allow flags in /etc/fstab to be improperly dropped on user-mountable volumes, allowing a user to gain root privileges.