[syslog-ng]Separate log messages

Hi, We have a Red Hat 7.3 Log server (using default syslogd) which are receiving all log messages from Linux and Solaris syslogd clients. I want syslogd to separate the log message file automatically based on each syslogd client hostname. Anyone knows how to do it? Could I change the name of log file to each_host_message. Thanks, Hong