[syslog-ng]problem with creating AF_INET socket at startup

Hi, I'm setting up a config with a frontal 'naked' linux RedHat 7.2 box / 2.4.18 (no X, no compiling tools, a basic firewall router) named celti000 I'd like to forward all the logs of celti000 on another linux box (RedHAt 7.2 / 2.4.18, with compiling tools). launching syslog-ng works on both machine, excpet on celti000, when I put this line in syslog-ng.conf : destination d_celti001 { udp("celti001" port (999)); }; if I have this line in my config file I get: error creating AF_INET socket (No such file or directory) any hints ? Thanks, Fred