Problems installing postgrey on CentOS 4.7

Hi,

I am running CentOS 4.7 (Final).

When trying to install postgrey I receive the following:

-----[snip]-----
Installing package(s) with command yum -y install postgrey ..

Error: Missing Dependency: perl(Net::Server::Daemonize) is needed by package postgrey
Error: Missing Dependency: perl(Net::Server::Multiplex) is needed by package postgrey
Error: Missing Dependency: perl(Net::Server) is needed by package postgrey
Setting up Install Process
Setting up repositories
Reading repository metadata in from local files
Parsing package install arguments
Resolving Dependencies
--> Populating transaction set with selected packages. Please wait.
---> Package postgrey.noarch 0:1.31-2.el4 set to be updated
--> Running transaction check
--> Processing Dependency: perl(Net::Server::Daemonize) for package: postgrey
--> Processing Dependency: perl(BerkeleyDB) for package: postgrey
--> Processing Dependency: perl(Net::Server::Multiplex) for package: postgrey
--> Processing Dependency: perl(Net::Server) for package: postgrey
--> Restarting Dependency Resolution with new changes.
--> Populating transaction set with selected packages. Please wait.
---> Package perl-BerkeleyDB.i386 0:0.34-2.el4.vm set to be updated
--> Running transaction check
--> Processing Dependency: perl(Net::Server::Daemonize) for package: postgrey
--> Processing Dependency: perl(Net::Server::Multiplex) for package: postgrey
--> Processing Dependency: perl(Net::Server) for package: postgrey
--> Finished Dependency Resolution

.. install failed!
-----[snip]-----

Additionally when trying to install perl-Net-Server I receive the following:

-----[snip]-----
[root@web2 /]# yum install perl-Net-Server
Setting up Install Process
Setting up repositories
Reading repository metadata in from local files
Parsing package install arguments
No Match for argument: perl-Net-Server
Nothing to do
-----[snip]-----

Any assistance would be greatly appreciated.

Thanks,
Simon