NRPE Plugin is not working

Nagios Nagios Plugins support
1

I’m using Centos 5.2 and Nagios 3.0.3 on my intel system. And Nrpe is also installed on CentOs 5.2 but in a remote place. I want to check remote machine through Nagios server in my office through Public IP. When we check command " /usr/local/nagios/libexec/check_nrpe -H xxx.xxx.xxx.xxx " on my nagios server machine it say’s “CHECK_NRPE: Socket timeout after 10 seconds” I’ve cross checked firewall on bothsides and disabled it.

          Is there any thing that i'm missing, please help me out

Thanks in advance.