NFS4 name resolving fails

Binary package hint: nfs-common

I wanted to set up a small file server. Since it is not acceptable for me to have the same UID on all clients I decided to use NFS4 which should be able to solve that. I started with Ubuntu 11.04 server.

What I did manage is access files (rw) if I have the same UID on client and server. If they differ I get an error message.

I find that a bit surprising since I have the most basic setup which should work without trouble.

/etc/exports on the server
/data 10.0.0.0/24(rw,sync,fsid=0,crossmnt,no_subtree_check)

/etc/idmapd.conf on client and server
[General]
Verbosity = 0
Pipefs-Directory = /var/lib/nfs/rpc_pipefs
Domain = local
[Mapping]
Nobody-User = nobody
Nobody-Group = nogroup

/etc/hosts on the server
127.0.0.1 localhost.local localhost
10.0.0.7 benjamin.local benjamin
10.0.0.10 zesi.local zesi
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

/etc/hosts on the client
127.0.0.1 localhost.local localhost
10.0.0.10 zesi.local zesi # Added by NetworkManager
10.0.0.7 benjamin.local benjamin
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

Hostnames on client and server (hostname command)
zesi benjamin

Dnsdomainname on client and server (dnsdomainname command)
local

But I get strange syslog entries
Jun 13 21:43:42 zesi rpc.idmapd[10766]: nss_getpwnam: name '0' does not map into domain 'local'
Jun 13 21:43:47 zesi rpc.idmapd[10766]: nss_getpwnam: name '1001' does not map into domain 'local'
Jun 13 21:43:47 zesi rpc.idmapd[10766]: nss_getpwnam: name '1002' does not map into domain 'local'
Jun 13 21:43:47 zesi rpc.idmapd[10766]: nss_getpwnam: name '1003' does not map into domain 'local'
Jun 13 21:43:47 zesi rpc.idmapd[10766]: nss_getpwnam: name '1004' does not map into domain 'local'