service = new Acmeco.AcmecoService();
service.Timeout = 10000;
service.Url = ConfigurationSettings.AppSettings["AcmecoWebServiceUrl"];
if you are using VS.NET, you can also change the "Url Behavior" from "Static" to "Dynamic" in the properties of the web service
see
http://www.aspalliance.com/shark/articles/WSDL/Wsdl.aspx