If you do a corporate CPAN, please do it properly!
It’s a good idea, but a completely wrong solution. If someone is going to implement this, the proper way is not creating a PAUSE and CPAN mirror or anything like it. Corporate requirements are different. What you really need is a revival of http://debian.pkgs.cpan.org/ and also complete repositories for RHEL5, Debian, Ubuntu LTS, SLES9/10 etc. Those can be mirrored at will by usual and well-tested tools.
Update: Removed last sentence, it’s been a “thinko” on my side :(