Hi,
Need help in udnerstanding the error type and resolving the same.​
System.CalloutException: IO Exception: Unable to tunnel through proxy. Proxy returns "HTTP/1.0 403 Forbidden

We are trying to integrate with Perlchain CPQ machine, There is no provision for passing the user name and password in the wsdl provided by CPQ. I have followed the link and tweaked to pass these two as part of header.
http://blog.dacology.com/callouts-from-salesforce-adding-soap-headers-for-wsse-security/

I'm still getting the error, 
System.CalloutException: IO Exception: Unable to tunnel through proxy. Proxy returns "HTTP/1.0 403 Forbidden

Need help in resolving this.

//Generated by wsdl2apex

public class xsServicesOp {

        public class Security {
            public UsernameToken usernameToken;
            private String[] usernameToken_type_info = new String[]{'UsernameToken','http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd','UsernameToken','0','1','true'};
            private String[] apex_schema_type_info = new String[]{'http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd','true','false'};
            private String[] field_order_type_info = new String[]{'usernameToken'};
        }
        public class UsernameToken {
            public String username;
            public String password;
            private String[] username_type_info = new String[]{'Username','http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd','string','0','1','true'};
            private String[] password_type_info = new String[]{'Password','http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd','string','1','1','true'};
            private String[] apex_schema_type_info = new String[]{'http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd','true','false'};
            private String[] field_order_type_info = new String[]{'username','password'};
        }  
    public class CreateOpportunityPortType {
        public String endpoint_x = //'http://localhost:8010/CreateOpptyMed/1';
           (I have replace endpoint with the correct url)
                                    
        public Map<String,String> inputHttpHeaders_x;
        public Map<String,String> outputHttpHeaders_x;
        public String clientCertName_x;
        public String clientCert_x;
        public String clientCertPasswd_x;
        public Integer timeout_x;
            //instantiate the header
            public UsernameToken userToken;
            public Security Header;
            private String Header_hns = 'Security=http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd';
            //end
        private String[] ns_map_type_info = new String[]{'http://www.test.machine/messages/opportunity/1', 'CdmMessagesOpport', 'http://www.test.machine/opportunity/1', 'CdmOpportunity', 'http://www.test.machine/services/opportunity/1', 'CdmServicesOpport', 'http://www.test.machine/common/1', 'CdmCommon', 'urn:codelist:ISO639-2-2002', 'CdmCodelist', 'http://www.test.machine/customer/1', 'CdmCustomer'};
        public CdmMessagesOpport.CreateOpportunityResponseMessageType CreateOpportunity(CdmOpportunity.OpportunityType Opportunity,CdmOpportunity.AccountType Account,CdmOpportunity.ProductsType[] Products) {
            CdmMessagesOpport.CreateOpportunityRequestMessageType request_x = new CdmMessagesOpport.CreateOpportunityRequestMessageType();
            request_x.Opportunity = Opportunity;
            request_x.Account = Account;
            request_x.Products = Products;
            CdmMessagesOpport.CreateOpportunityResponseMessageType response_x;
            Map<String, CdmMessagesOpport.CreateOpportunityResponseMessageType> response_map_x = new Map<String, CdmMessagesOpport.CreateOpportunityResponseMessageType>();
            response_map_x.put('response_x', response_x);
            
            userToken = new UsernameToken();
            userToken.username = 'onecanon';
            userToken.password = 'password';


            WebServiceCallout.invoke(
              this,
              request_x,
              response_map_x,
              new String[]{endpoint_x,
              '',
              'http://www.test.machine/services/opportunity/1',
              'CreateOpportunityRequestMessage',
              'http://www.test.machine/services/opportunity/1',
              'CreateOpportunityResponseMessage',
              'CdmMessagesOpport.CreateOpportunityResponseMessageType'}
            );
            response_x = response_map_x.get('response_x');
            return response_x;
        }
    }
}