[CentOS] rsyslog not loading relp

centos 6.4, setup to be syslog server. Doing remote syslog using tcp
works fine, so now want to add relp. I installed the rsyslog-relp
package and told rsyslog.conf to use it:

# RELP Syslog Server:
$ModLoad imrelp  # provides RELP syslog reception
$InputRELPServerRun 20514

when I restart rsyslog I am told it does not like my InputRELPServerRun line:

Oct 28 13:43:54 scan rsyslogd: [origin software="rsyslogd"
swVersion="5.8.10" x-pid="7102" x-info="http://www.rsyslog.com"] start
Oct 28 13:43:54 scan rsyslogd: the last error occured in
/etc/rsyslog.conf, line 23:"$InputRELPServerRun 20514"

Any clues?