The package fam-server from SuSE Linux 10.0 RC1 comes with the following file
/etc/xinet.d/fam:

$ cat /etc/xinetd.d/fam
# default: off
# description: The fam server answers requests via libfam.  \
#       It is used to report file or directory changes to monitoring \
#       clients. 
service fam
{
        socket_type     = stream
        protocol        = tcp
        wait            = yes
        group           = nobody
        server          = /usr/sbin/fam
        disable         = yes
        type            = RPC UNLISTED
        rpc_version     = 2
        rpc_number      = 391002
}

If I change "disable = yes" to "disable = yes" and reload xinetd, I still get a
message, that the user attribute is missing:

$ tail /var/log/messages|grep fam
Sep 28 13:15:31 chemnitz xinetd[3949]: Service fam missing attribute user -
DISABLING

Fedora Core 4 for instance uses "user = root".