RHEL5 Local YUM Repo

Create folder for repo.
# mkdir /var/install/RHEL5
Mount media with RHEL5.
# mount /dev/cdrom /media
Copy the content of the Server folder including repodata folder.
# cp -pr /media/RHEL_5xxx/Server/ /var/install/RHEL5
Create repo file for your new local repo folder. Make sure the file:/// path is correct and repo is enabled.
# vi /etc/yum.repos.d/rhel-local.repo
   [rhel-local]
   name=RHEL5 $releaserver - $basearch - Local Base
   baseurl=file:///var/install/RHEL5
   enabled=1
   gpgcheck=0
Check repo.
# yum repolist all

Installing VirtualBox Additions in RHEL5.5 VM (x86)

1. Install required packages.
[root@rhel5 Server]# rpm -ivh kernel-devel-2.6.18-194.el5.i686.rpm rpm -ivh gcc-4.1.2-48.el5.i386.rpm glibc-devel-2.5-49.i386.rpm glibc-headers-2.5-49.i386.rpm kernel-headers-2.6.18-194.el5.i386.rpm libgomp-4.4.0-6.el5.i386.rpm 
2. Mount VBoxGuestAdditions.iso and copy an installation file.
[root@rhel5 ~]# cd /media/VBOXADDITIONS_3.2.6_63112/
[root@rhel5 VBOXADDITIONS_3.2.6_63112]# ls
[root@rhel5 VBOXADDITIONS_3.2.6_63112]# cp VBoxLinuxAdditions-x86.run /tmp/
[root@rhel5 VBOXADDITIONS_3.2.6_63112]# cd /tmp/
3. Install Additions.
[root@rhel5 tmp]# ./VBoxLinuxAdditions-x86.run 
4. Reboot.
[root@rhel5 tmp]# reboot