Tengo 2 eventos en mi archivo Global.asax.cs

WSFederationAuthenticationModule_SecurityTokenValidated y WSFederationAuthenticationModule_RedirectingToIdentityProvider

l motor wif no llama a @WSFederationAuthenticationModule_RedirectingToIdentityProvider. ¿Por qué

public class MvcApplication : System.Web.HttpApplication
{ 
    void WSFederationAuthenticationModule_SecurityTokenValidated(object sender, SecurityTokenValidatedEventArgs e)
    {
        FederatedAuthentication.SessionAuthenticationModule.IsSessionMode = true;
    }


    void WSFederationAuthenticationModule_RedirectingToIdentityProvider(object sender, RedirectingToIdentityProviderEventArgs e)
    {
        //some code
    }
}

Esta es la sección microsoft.identityModel en web.config

<microsoft.identityModel>
        <service saveBootstrapTokens="true">
          <audienceUris mode="Never">

          </audienceUris>
          <federatedAuthentication>
            <wsFederation passiveRedirectEnabled="true" issuer="http://localhost/dss.web.sts.tokenbaker/" realm="http://localhost/dss.web.frontend" requireHttps="false" />
            <cookieHandler requireSsl="false" />



          </federatedAuthentication>

          <issuerNameRegistry type="Microsoft.IdentityModel.Tokens.ConfigurationBasedIssuerNameRegistry, Microsoft.IdentityModel, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
            <trustedIssuers>
              <add thumbprint="308efdee6453fff68c402e5eceee5b8bb9eaa619" name="servcert" />

            </trustedIssuers>
          </issuerNameRegistry>
        </service>
      </microsoft.identityModel>