HDA unreadable & NTFS partition with fatal errors ?

Hi list !

I'm currently doing auditing a hacked server (Win 2K3 SP 1) and something odd 
happends on a partition with dada (D:):

- Under Win 2K3 (after booting with it), the partition is visible and found as 
"free space", but no way to create a partition on it (fatal error occurs during 
the task).
- Under Win 2K3 (with the recuperation console), the partition is visible as 
"D:", but no way either to check the volume with chkdsk, chkntfs ot any command 
like that.
- As there ware some free space on the hard disk (another than the D: 
partition), I tried to set up a Fedora Core 4 on it, but failed when tried to 
install it with Druid: "HDA is not readeable"

I did not tried to format the D: partition as I want first to try to get the 
data on it to try to understand what happened.

Anyone has an idea of how can I make the partition be readable again without 
formatting it (what can I do if booting under another OS, or is there a useful 
tool for recovering data on unreadable partition) ? I have obviously full 
access to the box, but I am really at a loss for an idea to access trhe 
partition :(

Any help will be appreciated, I'm quite stuck with this :(

Thx !