How do I flush the NFS cache?

Basically I have a read-only[HTML][/HTML] file system exported. A script ran in a client that tried to change the file system and could't as expected. I updated the files in the server. Now I get a interesting thing:

ls: name_of_file: file not found
total: 666
file1 file2 file3

Interesting enough it only happens in the node that ran the script, so I conclude that the local cache is bad. I can however see the updates in all other nodes. Reading through the internet I found a bug report about the subject and it presented the solution with doing a flush with nfsutils. However the link in the nfs homepage doesn't work, the debian apt-cache doesn't show a nfs-util package but I see security advisories on it by debian.

So if someone could give me a alternative solution or a repositiory that has a utility to flush the NFS cache I would apreciate it.

PS: I can't reboot the system as it is a production system and this doesn't justify bringing it down.