NFS/Apache Permissions

[Paul M Foster <paulf@quillandmouse.com>]

Two machines running Debian 3.0.

spaceghost is a file/webserver on the local network (behind a firewall).
Permissions/ownership on some directories:

drwxrwxr-x /var/www root web
drwxrwxr-x /var/www/mywebsite root web

User on this machine is paulf, which belongs to group web.

rocky is a desktop workstation, also on the local network.
Permissions/ownership on some directories:

drwxr-xr-x /var/www root root
drwxrwxr-x /var/www/mysebsite paulf paulf

User on this machine is paulf.

Spaceghost's /var/www is mounted via nfs at /mnt/www on rocky. fstab
line is:

spaceghost:/var/www /mnt/www nfs defaults,rw 0 0

Mounting goes fine, and I can see the directories from rocky. I want to
copy files from /var/www/mywebsite on rocky to /var/www/mywebsite on
rocky to /var/www/mywebsite on spaceghost. However, when I try to do
this, I cannot, and I get a permissions problem.

Any clues?

Paul