RedHat : Impossible d'installer le paquetage GNOME Desktop Environment

J'ai installé le paquetage GNOME Desktop Environment sur ma machine fonctionnant sous Red Hat version 6.4.

more /etc/redhat-release 
Red Hat Enterprise Linux Server release 6.4 (Santiago)

A la fin de l'installation, j'ai reçu une erreur concernant l'absence de RPM- GPG-KEY-oracle répertoire.

    [Errno 14] Could not open/read file:///etc/pki/rpm-gpg/RPM-  GPG-KEY-oracle

Comment puis-je résoudre ce problème ?

[root@MY_BABY ~]#  yum groupinstall "X Window System" "GNOME Desktop Environment"
Loaded plugins: product-id, security, subscription-manager
This system is receiving updates from Red Hat Subscription Management.
ol6_UEK_latest                    | 1.2 kB     00:00
ol6_latest                        | 1.4 kB     00:00
rhel-6-server-rpms                | 3.7 kB     00:00
rhel-6-server-rpms/primary_db     |  30 MB     00:07   

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                                                                                           1.8 MB/s |  34 MB     00:18     
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID ec551f03: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle

GPG key retrieval failed: [Errno 14] Could not open/read file:///etc/pki/rpm-gpg/RPM-  GPG-KEY-oracle

J'ai aussi essayé ceci

wget http://public-yum.oracle.com/RPM-GPG-KEY-oracle-el5
--2015-01-05 13:28:14--  http://public-yum.oracle.com/RPM-GPG-KEY-oracle-el5
Resolving public-yum.oracle.com... 82.166.201.211
Connecting to public-yum.oracle.com|82.166.201.211|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1397 (1.4K) [text/plain]
Saving to: âRPM-GPG-KEY-oracle-el5.1â 0s  

rpm --import ./RPM-GPG-KEY-oracle-el5

mais je n'ai toujours pas le répertoire sous /etc/pki/rpm-gpg/ .

ls /etc/pki/rpm-gpg/RPM-  GPG-KEY-oracle

C'est ce que j'ai dans /etc/yum.repos.d :

# ls /etc/yum.repos.d
mirrors-rpmforge          public-yum-ol6.repo  rpmforge.repo             swp-default-    LVS-repo.repo
mirrors-rpmforge-extras   redhat.repo          service-cd-LVS-repo.repo  swp-default-    repo.repo
mirrors-rpmforge-testing  rhel-source.repo     service-cd-repo.repo      swp-vmware-    tools-repo.repo