LinuxQuestions.org - RHEL WS4: change installation path

I get this message in the add/remove software program
"Red Hat Enterprise Linux 4" disk 3 needed to install packages
Insert the disk and press OK.

I have the disks, that's not the problem..

the problem is my old disk drive is broken and i installed a new external disk drive which works flawlessly.

Red Hat keeps looking at my old disk drive for the cds even though i put them in the working external one.

How do i tell Red Hat that to look at the external as my installation path?

UPDATE:
ok, there is a program called system-config-packages with a couple usage options...
/media/cdrecorder is my external cdrom's path
i tried the following with all resulting in failures:
system-config-packages --tree=/media/cdrecorder/
system-config-packages --tree=/media/cdrecorder/Redhat/
system-config-packages --tree=/media/cdrecorder/Redhat/RPMS/
system-config-packages --isodir=/media/cdrecorder/
system-config-packages --isodir=/media/cdrecorder/Redhat/
system-config-packages --isodir=/media/cdrecorder/Redhat/RPMS/

UPDATE 2:
running system-config-packages in terminal mode allowed me to see some feedback of what was going on.. I decided to update my system with k3b. It needed 2 packages to install. here's what the terminal said:

Unable to get lock on device /dev/hdc: cd devs locked by system-config-packageshal devs is {'/dev/scd0': '/media/cdrom'}
...
exception while mounting: (16, 'Device or resource busy')
looking for me in /etc/mtab
dev is: /dev/scd0, where is: /media/cdrecorder
/dev/mapper/VolGroup00-LogVol00 / ext3 rw 0 0
none /proc proc rw 0 0
none /sys sysfs rw 0 0
none /dev/pts devpts rw,gid=5,mode=620 0 0
/dev/sda1 /boot ext3 rw 0 0
none /dev/shm tmpfs rw 0 0
none /proc/sys/fs/binfmt_misc binfmt_misc rw 0 0
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs rw 0 0
/dev/scd0 /media/cdrecorder iso9660 ro,nosuid,nodev,fscontext=system_u:object_r:removable_t,user=baxi 0 0

found it
trying to mount /dev/scd0
mounted it
trying to mount /dev/scd0
something is mounted
mounted it