Moderation.php failure

I have searched high and low through the forums for an answer to this.
This issue came up in 2.0.5 and continues in 2.1
I have a client with about 400 comments in moderation. (I told him this is to many to save) We have worked it down to only those ready to delete. Via the edit comment page.
Any action taken (approve/spam/delete/defer) all have the same result. After you click ‘moderate comments’. A blank page appears and no action is taken. I have restored the moderation.php file from a fresh download. No help.
My servers are on php4.4.4
I have optimized tables etc…
No comment plugins installed aside from Akismet.
Any help would be… well you know 😉

If I missed a thread that applies. Please point this lost soul in the right direction.

Any Idea as to how I can resolve this issue?

Thanks in advance..

Jon