syslog-ng

Pas de bol, redhat n'a pas compris qu'aujourd'hui la mode, c'était syslog-ng à la place de syslog, tu trouveras des paquets là :
http://www.silfreed.net/download/repo/rhel/
Pense à désactiver selinux sinon tu vas passez des heures à faire marcher le package.
Ensuite avec syslog-ng, tu peux faire une config vachement bien comme j'ai sur un serveur centos 5 (log stockés sur une grosse partition /srv/log) :

options {
sync (0);
time_reopen (10);
log_fifo_size (1000);
long_hostnames (off);
use_dns (no);
use_fqdn (yes);
create_dirs (yes);
perm(0640);
dir_perm(0750);
keep_hostname (no);
group(loghost);
dir_group(loghost);
# ts_format(iso);
};

source s_sys {
file ("/proc/kmsg" log_prefix("kernel: "));
unix-stream ("/dev/log");
internal();
};

source s_remote {
udp(ip(xxx.xxx.xxx.xxx);
udp6(ip(xxxx:xxxx:xxxx:xxxx::xxxx));
udp6(ip(::1));
tcp(ip(xxx.xxx.xxx.xxx) max-connections(100));
tcp6(ip(xxxx:xxxx:xxxx:xxxx::xxxx) max-connections(100));
tcp6(ip(::1) max-connections(100));
};

destination d_clients_fac {
file("/srv/log/HOSTS/${HOST}/${R_MONTH}-month/${R_DAY}-day/${FACILITY}-${R_YEAR}"
template("$ISODATE <$PRIORITY> $HOST $MSG\n")
template_escape(no)
);
};
destination d_tcp { tcp6("serveurlog"); };

destination d_cons { file("/dev/console"); };
destination d_mesg { file("/var/log/messages"); };
destination d_auth { file("/var/log/secure"); };
destination d_mail { file("/var/log/maillog" sync(10)); };
destination d_spol { file("/var/log/spooler"); };
destination d_boot { file("/var/log/boot.log"); };
destination d_cron { file("/var/log/cron"); };
destination d_kern { file("/var/log/kern"); };
destination d_mlal { usertty("*"); };

filter f_filter1 { facility(kern); };
filter f_filter2 { level(info..emerg) and
not (facility(mail)
or facility(authpriv)
or facility(cron)); };
filter f_filter3 { facility(authpriv); };
filter f_filter4 { facility(mail); };
filter f_filter5 { level(emerg); };
filter f_filter6 { facility(uucp) or
(facility(news)
and level(crit..emerg)); };
filter f_filter7 { facility(local7); };
filter f_filter8 { facility(cron); };

#log { source(s_sys); filter(f_filter1); destination(d_cons); };
log { source(s_sys); filter(f_filter1); destination(d_kern); };
log { source(s_sys); filter(f_filter2); destination(d_mesg); };
log { source(s_sys); filter(f_filter3); destination(d_auth); };
log { source(s_sys); filter(f_filter4); destination(d_mail); };
log { source(s_sys); filter(f_filter5); destination(d_mlal); };
log { source(s_sys); filter(f_filter6); destination(d_spol); };
log { source(s_sys); filter(f_filter7); destination(d_boot); };
log { source(s_sys); filter(f_filter8); destination(d_cron); };

log { source(s_remote); destination(d_clients_fac); };
log { source(s_sys); destination(d_tcp); };