invalid statement in peer declaration for omapi-port

[michael kapelko]

I have the following config:

failover peer "elt-dhcp" {
    primary;
    address 10.102.100.73;
    port 519;
    peer address 10.102.101.23;
    peer port 520;
    max-response-delay 180;
    max-unacked-updates 10;
    split 255;
    mclt 180;
    omapi-port 719;
}
include "/tmp/dhcpd.master1";

which works without problems when omapi-port is omitted.
When I add it, I get errors:
/tmp/dhcpd.conf1 line 12: invalid statement in peer declaration
    omapi-port
    ^
/tmp/dhcpd.master1 line 38: failover peer elt-dhcp: not found
		failover peer "elt-dhcp"
                              ^
/tmp/dhcpd.master1 line 44: failover peer elt-dhcp: not found
		failover peer "elt-dhcp"
                              ^
- - -
How to enable OMAPI?
Thainks/