JetPack Plugin activation & self signed certificate problem!

Recently I have taken initiative to install & activate Jetpack plugin in my self hosted WordPress blog. <snip/>
I already installd it but I am facing problem with activiting it with wordpress.com. When I press to connect with wordpress.com then I see suggestion as follows:
Jetpack could not contact WordPress.com: register_http_request_failed.
This usually means something is incorrectly configured on your web host.
SSL certificate problem: self signed certificate in certificate chain

(Debug-CERT: 0)

Can anyone please help me how can I solve this problem?