OS: Ubuntu 12.10 Server 64bits

I've installed Icinga, with ido2db, pnp4nagios and icinga-web (last release, following the instruction given in the documentation, installation with apt, etc). I am using icinga-web to monitor my hosts. For the moment, I have just my localhost, and all is perfect.

I am trying to add a host and monitor it with NRPE (version 2.12):

root@server:/etc/icinga# /usr/lib/nagios/plugins/check_nrpe -H client
NRPE v2.12

The configuration looks good.

I've created a file in /etc/icinga/objects/client.cfg as below on the server:

root@server:/etc/icinga/objects# cat client.cfg
define host{
 use generic-host ; Name of host template to use
 host_name client
 alias client.toto
 address xx.xx.xx.xx
 }

# Service Definitions
define service{
 use generic-service
 host_name client
 service_description CPU Load
 check_command check_nrpe_1arg!check_load
 }

define service{

 use generic-service
 host_name client
 service_description Number of Users
 check_command check_nrpe_1arg!check_users
 }

And add in my /etc/icinga/commands.cfg:

# this command runs a program $ARG1$ with no arguments
define command {
 command_name check_nrpe
 command_line /usr/lib/nagios/plugins/check_nrpe -H $HOSTADDRESS$ -c $ARG1$ -a $ARG2$
}

# this command runs a program $ARG1$ with no arguments
define command {
 command_name check_nrpe_1arg
 command_line /usr/lib/nagios/plugins/check_nrpe -H $HOSTADDRESS$ -c $ARG1$
}

But it does not work.

These are the logs from the client:

Dec 3 19:45:12 client nrpe[604]: Connection from xx.xx.xx.xx port 32641
Dec 3 19:45:12 client nrpe[604]: Host address is in allowed_hosts
Dec 3 19:45:12 client nrpe[604]: Handling the connection...
Dec 3 19:45:12 client nrpe[604]: Host is asking for command 'check_users' to be run...
Dec 3 19:45:12 client nrpe[604]: Running command: /usr/lib/nagios/plugins/check_users -w -c
Dec 3 19:45:12 client nrpe[604]: Command completed with return code 3 and output: check_users: Warning t hreshold must be a positive integer#012Usage:check_users -w  -c 
Dec 3 19:45:12 client nrpe[604]: Return Code: 3, Output: check_users: Warning threshold must be a positive integer#012Usage:check_users -w  -c 

Dec 3 19:44:49 client nrpe[32582]: Connection from xx.xx.xx.xx port 32129
Dec 3 19:44:49 client nrpe[32582]: Host address is in allowed_hosts
Dec 3 19:44:49 client nrpe[32582]: Handling the connection...
Dec 3 19:44:49 client nrpe[32582]: Host is asking for command 'check_load' to be run...
Dec 3 19:44:49 client nrpe[32582]: Running command: /usr/lib/nagios/plugins/check_load -w -c
Dec 3 19:44:49 client nrpe[32582]: Command completed with return code 3 and output: Warning threshold mu st be float or float triplet!#012#012Usage:check_load [-r] -w WLOAD1,WLOAD5,WLOAD15 -c CLOAD1,CLOAD5,CLO AD15
Dec 3 19:44:49 client nrpe[32582]: Return Code: 3, Output: Warning threshold must be float or float trip let!#012#012Usage:check_load [-r] -w WLOAD1,WLOAD5,WLOAD15 -c CLOAD1,CLOAD5,CLOAD15
Dec 3 19:44:49 client nrpe[32582]: Connection from xx.xx.xx.xx closed.

Have you any ideas?