Log of who accessed a file on the network?

Hi.

I have a 2003 AD domain with W2K3 servers and XP clients. From time to time, someone might make undedesireable changes to a file, and then when someone else opens the file and sees this, they want to know who opened it last? Or, if its over a weekend, who opened it 3 days ago in a specific time frame.

I searched the net looking for tips regarding this, and everything just keeps pointing to the fact that you can see who has a file open and that you can close open files etc. This is not what Im looking for. I want to know if there is some way of tracking file usage on the network.

Thanks