problem in calling ME webservice through HTTP POST action

Hi Experts,

I am trying to call SAP ME WebService through HTTP POST Action in SAP MII transaction. I am getting the following message."errror occured while trying to connect to server Exception". MII sever is at Onsight and SAP ME at on my local machine. But both are in same network.I am connecting through VPN. Is there any proxy settings needs to be configured.

Thanks.