ref : http://kerneltrap.org/mailarchive/freebsd-bugs/2007/10/27/362534

www# cat /var/log/messages
May 25 21:19:31 www root: /etc/rc: WARNING: /webserver/jails/home/dev has symlink as parent - not starting jail webserver

what happen? that was because

www# cat /etc/rc.conf |grep root
jail_webserver_rootdir="/webserver/jails/home/" #this directory wrong
www#

www# cd /webserver/jails/
www# ls
.cshrc          boot            lib             proc            sys
.profile        dev             libexec         rescue          tmp
COPYRIGHT       etc             media           root            usr
bin             home            mnt             sbin            var
www#

change it to

jail_webserver_rootdir="/webserver/jails/"