To enable core file creation for daemons:

# vi /etc/security/limits.conf
…
#* soft core 0
* soft core unlimited
…

# vi /etc/sysctl.conf
…
kernel.core_pattern = /tmp/core-%e-%s-%u-%g-%p-%t
fs.suid_dumpable = 2
…

# vi /etc/sysconfig/init
…
DAEMON_COREFILE_LIMIT=’unlimited’
…

# sysctl -p

To enable core dumps for xinetd services, I just needed to install the Automatic Bug Report Tool (abrt), and start the service:

# yum install abrt-desktop

# service abrtd start

Some command line commands:
# abrt-cli –list
# abrt-cli –report crash_id