NPC2.0 and ndoutils ERROR, Still unable to connect to data s

[lewise.liu]

hi guys
Recently I have been busy in deploying the cacti+nagios monitor system.But at npc 2.0 model,I meet a odd error:
[1215233124] ndomod: Still unable to connect to data sink. 2297621 items lost, 5000 queued items to flush.(in nagios.log).
Cacti can works well ,and nagios can works normally also.But the NPC web is blank and has none data on the hosts and services.
At the same time ,I find the table Nagios_hosts and Nagios_services have rows. which is so odd.
The upper error happen after I deployed the ndomon and ndo2db to nagios.
My deploying version be as below:
Cacti 0.8.7b
Cacti Plugin Architecture v2.0
NPC 2.0
ndoutils-1.4b7
php 5.2
mysql 5.0
nagios-3.0
Perhaps somethings is wrong with the ndoutils.But I have reinstalled and deployed the ndoutils for 3 times. The problem exists also.
The problem has suffer me for one weeks.
Any suggest and help is appreciated.