kterm-6.2.0-10.i386.rpm in RedHat-6.1J
Kterm doesn't need a setuid root permission, but a permisson of the
command is "-rws--x--x". It should be the same as xterm's one.
$ cat /etc/redhat-release
Red Hat Linux release 6.1J (Cartman)
$ ls -l /usr/bin/X11/xterm
-rwxr-xr-x 2 root root 164328 Sep 25 07:21 /usr/bin/X11/xterm
$ ls -l /usr/bin/X11/kterm
-rws--x--x 1 root root 140660 Oct 7 13:10 /usr/bin/X11/kterm
Both of xterm and kterm invoke /usr/sbin/utempter that can
access /var/run/utmp. But only xterm doesn't have the root permission.
I'm sure that kterm can access utmp without the root permission.
Fixed in rawhide.