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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.9) Gecko/20061206 Firefox/1.5.0.9

Description of problem:
[root@leonli2 tree-i386]# yum update
Loading "installonlyn" plugin
Loading "rhnplugin" plugin
Setting up Update Process
Setting up repositories
rhel-i386-server-5-beta   100% |=========================|  950 B    00:00
Reading repository metadata in from local files
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package ImageMagick.i386 0:6.2.8.0-3.fc6 set to be updated
--> Running transaction check

Dependencies Resolved

=============================================================================
 Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
 ImageMagick             i386       6.2.8.0-3.fc6    rhel-i386-server-5-beta  3.3 M

Transaction Summary
=============================================================================
Install      0 Package(s)
Update       1 Package(s)
Remove       0 Package(s)

Total download size: 3.3 M
Is this ok [y/N]: y
Downloading Packages:
warning: rpmts_HdrFromFdno: Header V3 DSA signature: NOKEY, key ID 897da07a


GPG key retrieval failed: [Errno 5] OSError: [Errno 2] No such file or directory: '/etc/pki/rpm-gpg/RPM-GPG-KEY-beta'

Version-Release number of selected component (if applicable):
RHEL 4.92 (Tikanga) 20070112.3

How reproducible:
Always


Steps to Reproduce:
1.yum update 
2.
3.

Actual Results:
[root@leonli2 tree-i386]# yum update
Loading "installonlyn" plugin
Loading "rhnplugin" plugin
Setting up Update Process
Setting up repositories
rhel-i386-server-5-beta   100% |=========================|  950 B    00:00
Reading repository metadata in from local files
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package ImageMagick.i386 0:6.2.8.0-3.fc6 set to be updated
--> Running transaction check

Dependencies Resolved

=============================================================================
 Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
 ImageMagick             i386       6.2.8.0-3.fc6    rhel-i386-server-5-beta  3.3 M

Transaction Summary
=============================================================================
Install      0 Package(s)
Update       1 Package(s)
Remove       0 Package(s)

Total download size: 3.3 M
Is this ok [y/N]: y
Downloading Packages:
warning: rpmts_HdrFromFdno: Header V3 DSA signature: NOKEY, key ID 897da07a


GPG key retrieval failed: [Errno 5] OSError: [Errno 2] No such file or directory: '/etc/pki/rpm-gpg/RPM-GPG-KEY-beta'


Expected Results:
[root@leonli2 rpm-gpg]# yum update
Loading "installonlyn" plugin
Loading "rhnplugin" plugin
Setting up Update Process
Setting up repositories
rhel-i386-server-5-beta   100% |=========================|  950 B    00:00
Reading repository metadata in from local files
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package ImageMagick.i386 0:6.2.8.0-3.fc6 set to be updated
--> Running transaction check

Dependencies Resolved

=============================================================================
 Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
 ImageMagick             i386       6.2.8.0-3.fc6    rhel-i386-server-5-beta  3.3 M

Transaction Summary
=============================================================================
Install      0 Package(s)
Update       1 Package(s)
Remove       0 Package(s)

Total download size: 3.3 M
Is this ok [y/N]: y
Downloading Packages:
warning: rpmts_HdrFromFdno: Header V3 DSA signature: NOKEY, key ID 897da07a
Importing GPG key 0x897DA07A "Red Hat, Inc. (Beta Test Software) <rawhide>"
Is this ok [y/N]: y
Running Transaction Test
Finished Transaction Test
Transaction Test Succeeded
Running Transaction
  Updating  : ImageMagick                  ######################### [1/2]
  Cleanup   : ImageMagick                  ######################### [2/2]

Updated: ImageMagick.i386 0:6.2.8.0-3.fc6
Complete!

Additional info:
After I run 

[root@leonli2 tree-i386]# cd /etc/pki/rpm-gpg/
[root@leonli2 rpm-gpg]# cp RPM-GPG-KEY-redhat-beta  RPM-GPG-KEY-beta

it works well as expected results