SSO authentication using C# soap client

hi all,

Anyone know how I can establish and SSO connection using soap in a third party c# web client.

I noticed with the rest API doco there is the following reference.

URI ssoUri = URI.Create(https://ssoInstance:7444/ims/STSService?wsdl");

Before I waste my time does anyone know if this is suitable via the soap client as well? I guess it is but rather than waste a day I figure I would ask first.