// There is an issue here. It seems that the only way to set the endpoint
// alias is through the jopenid-1.07.jar openid-providers.properties,
// but we would to to configure the provider properties through gpt.xml
//Endpoint endpoint = manager.lookupEndpoint(provider.getAuthenticationUrl());
Endpoint endpoint = manager.lookupEndpoint(op);
Association association = manager.lookupAssociation(endpoint);
request.getSession().setAttribute(ATTR_MAC,association.getRawMacKey());
request.getSession().setAttribute(ATTR_ALIAS,endpoint.getAlias());
url = manager.getAuthenticationUrl(endpoint,association);