Before you start using the SSO API, you should consider using the TAS3 SSO servlet. tas3_sso_servlet.class can be configured to Tomcat or other servlet container to implement SSO for payload servlets. Internally the SSO servlet calls tas3_sso().
Similar module is planned (as of 2009) for Responder implementation. The pushable filter module for servlet environments (e.g. Tomcat) will wrap tas3.wsp_validate() and tas3.wsp_decorate(). The filter module allows some web services to be TAS3 enabled without modification to the application code.