Well I have install a FOG 0.30 in RHEL 6.3, and you must make some changes:

1º) Disable firewall and selinux
[I]#sudo selinuxenabled; echo $?[/I]
if the echo returns 0, the SELinux is enable and you must disable it
[I]#sudo /etc/selinux/confi[/I]g
change the value to disabled
[I]#sudo setenforce 0[/I]
[I]#reboot[/I]
2º) Download the FOG code
3º) You must make some change in some config files:
3.1) Unziped_folder/lib/redhat/config.sh
[I]packages=“httpd [B]php php-gd php-cli[/B] mysql mysql-server [B]php-mysql[/B] tftp-server nfs-utils vsftpd net-tools wget xinetd tar gzip make m4 gcc gcc-c++ htmldoc perl perl-Crypt-PasswdMD5 lftp clamav [B]clamd[/B]”;[/I]
I change the next packages: php53 -> php and add clamd. The php-gettext not exists in RHEL.
4º) download and install the next repositories:
[I]#wget [url]http://apt.sw.be/redhat/el6/en/x86_64/rpmforge/RPMS/rpmforge-release-0.5.2-1.el6.rf.x86_64.rpm[/url][/I]
[I]#wget [url]http://mirror.uv.es/mirror/fedora-epel/6/i386/epel-release-6-8.noarch.rpm[/url][/I]
[I]#sudo rpm -i --quiet rpmforge-release-0.5.2-1.el6.rf.x86_64.rpm[/I]
[I]#sudo rpm -i --quiet epel-release-6-8.noarch.rpm[/I]
The EPEL repository is necesary to install htmldoc package.
5º) Run installfog.sh to install FOG
6º) You must config timezone in your php.ini:
[I]#sudo vim /etc/php.ini[/I]
In my case:
date.timezone = “Europe/Madrid”
[I]#/etc/init.d/httpd restart[/I]

Some issues:
*During the install process appears the next error:
[I]Setting up and starting NFS Server…Failed![/I]
Solution:
[I]#sudo service rpcbind start[/I]
*I have config the logwatch to see the freshclam messages, to config it:
Edit the [I]/etc/logwatch/conf/logwatch.conf[/I] file
Add the next line:
[I]MailTo = [EMAIL]miemailaddress@mydomain.com[/EMAIL][/I] (<== your email)
if you don’t want the logwatch messages delete the [I]/etc/cron.daily/0logwatch[/I] file

In logwatch messages appears the ext error:
[I]Notifyclam error[/I]
Solution:
Edit the [I]/etc/freshclam.conf[/I], uncomment and config the next line:
[I]NotifyClamd /etc/clamd.conf[/I]
[I] Error: clamd was not notified can’t connect to clamd through /var/run/clamav/clamd.sock[/I]
Solution: sudo touch /var/lib/clamav/clamd.sock sudo chown clam:clam /var/lib/clamav/clamd.sock