change webmin port howto
Edit /etc/xinetd.conf and add a section like : service webmin
{
user = root
env = LANG=
port = 10000
socket_type = stream
protocol = tcp
wait = no
disable = no
type = UNLISTED
server = /usr/libexec/webmin/miniserv.pl
server_args = /etc/webmin/miniserv.conf
}