So check this out:

root@pulsar /home #> yum install perl-Digest-SHA1 perl-Net-DNS
Setting up Install Process
Setting up Repos
core                      100% |=========================|  951 B    00:00     
testing                   100% |=========================| 1.1 kB    00:00     
Reading repository metadata in from local files
core      : ################################################## 187/187
testing   : ################################################## 1781/1781
Excluding Packages in global exclude list
Finished
Parsing package install arguments
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Downloading header for perl-Digest-SHA1 to pack into transaction set.
error: rpmpkgRead: Header: (null)
perl-Digest-SHA1-2.11-1.c 100% |=========================| 2.5 kB    00:00     
error: rpmpkgRead: Header: (null)
---> Package perl-Digest-SHA1.noarch 0:2.11-1.caos set to be updated
---> Downloading header for perl-Net-DNS to pack into transaction set.
error: rpmpkgRead: Header: (null)
perl-Net-DNS-0.60-1.caos. 100% |=========================|  15 kB    00:00     
error: rpmpkgRead: Header: (null)
---> Package perl-Net-DNS.x86_64 0:0.60-1.caos set to be updated
--> Running transaction check
--> Processing Dependency: perl(Net::IP) for package: perl-Net-DNS
--> Processing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/Digest for package: perl-Digest-SHA1
Importing Additional filelist information for dependency resolution
core      : ################################################## 187/187
testing   : ################################################## 1781/1781
--> Processing Dependency: perl(Digest::HMAC_MD5) for package: perl-Net-DNS
--> Processing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/auto/Digest/SHA1 for package: perl-Digest-SHA1
Importing Additional filelist information for dependency resolution
--> Restarting Dependency Resolution with new changes.
--> Populating transaction set with selected packages. Please wait.
error: rpmpkgRead: Header: (null)
error: rpmpkgRead: Header: (null)
---> Package perl-Digest-SHA1.noarch 0:2.11-1.caos set to be updated
---> Downloading header for perl-Digest-HMAC to pack into transaction set.
error: rpmpkgRead: Header: (null)
perl-Digest-HMAC-1.01-5.n 100% |=========================| 3.0 kB    00:00     
error: rpmpkgRead: Header: (null)
---> Package perl-Digest-HMAC.noarch 0:1.01-5 set to be updated
---> Downloading header for perl-Net-IP to pack into transaction set.
error: rpmpkgRead: Header: (null)
perl-Net-IP-1.25-1.caos.n 100% |=========================| 2.3 kB    00:00     
error: rpmpkgRead: Header: (null)
---> Package perl-Net-IP.noarch 0:1.25-1.caos set to be updated
error: rpmpkgRead: Header: (null)
error: rpmpkgRead: Header: (null)
---> Package perl-Net-DNS.x86_64 0:0.60-1.caos set to be updated
--> Running transaction check
--> Processing Dependency: /usr/lib/perl5/vendor_perl/5.8.5/Net for package: perl-Net-IP
Importing Additional filelist information for dependency resolution
--> Processing Dependency: /usr/lib/perl5/vendor_perl/5.8.5/Digest for package: perl-Digest-HMAC
Importing Additional filelist information for dependency resolution
--> Processing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/Digest for package: perl-Digest-SHA1
Importing Additional filelist information for dependency resolution
--> Processing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/auto/Digest/SHA1 for package: perl-Digest-SHA1
Importing Additional filelist information for dependency resolution
--> Finished Dependency Resolution
Error: Missing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/Digest is needed by package perl-Digest-SHA1
Error: Missing Dependency: /usr/lib64/perl5/vendor_perl/5.8.5/x86_64-linux-thread-multi/auto/Digest/SHA1 is needed by package perl-Digest-SHA1
Error: Missing Dependency: /usr/lib/perl5/vendor_perl/5.8.5/Net is needed by package perl-Net-IP
Error: Missing Dependency: /usr/lib/perl5/vendor_perl/5.8.5/Digest is needed by package perl-Digest-HMAC

The "error: rpmpkgRead: Header: (null)" messages are cosmetically bad
but functionally irrelevant.  The errors at the bottom, however,
indicate that parent directory dependencies seem to have somehow been
re-activated.  Weren't these turned off by default for 5.0, or am I
confused?

Michael

-- 
Michael Jennings (a.k.a. KainX)  http://www.kainx.org/  <mej@kainx.org>
Linux Server/Cluster Admin, LBL.gov       Author, Eterm (www.eterm.org)
-----------------------------------------------------------------------
 "Don't go making all these promises you know you cannot keep.
  There's a time to play a king and a time to be the thief.  'Cause
  if you're making all these promises you know you cannot keep, you
  know time will be the thief, and your fallen king will end up
  alone."                                 -- Savage Garden, "Promises"