I just tried the same on my latpop (MacOSX 12.4) and it worked flawlessly:

ritt@MBP14 build % echo "blah" | ./elog -h 127.0.0.1 -p 8080 -l demo -r 2 -x
Message successfully transmitted, ID=3
ritt@MBP14 build % host 127.0.0.1
Host 1.0.0.127.in-addr.arpa. not found: 3(NXDOMAIN)
ritt@MBP14 build % echo "blah" | ./elog -h localhost -p 8080 -l demo -r 2 -x
Message successfully transmitted, ID=4
ritt@MBP14 build %

So have you tried with the "-v" flag? Maybe your network is not correctly configured. You can also try the "curl" utility (see elog:68597), maybe you see some different error there. You get that via MacPorts.

Stefan