SimpleSamlPHP - SimpleSAMLSessionID empty

Question

We are currently setting up SAML authentication for the first time, due to a third-partner request.

To integrate some components they have writen, we need to provide some information from $_COOKIE[] after our customer have logged in : SimpleSAMLAuthToken and SimpleSAMLSessionID.

However, the second field seems not to be set by SimpleSamlPHP on our installation :

  $as = new SimpleSAML_Auth_Simple($url_saml);
  $as->requireAuth();
  print_r($_COOKIE);

gives us

Array
(
    [PHPSESSID] => r2st6fpu7ju2801cepl3d0****
    [SimpleSAMLAuthToken] => _e4eceb095eb14e2ab9fc4c53a65d1358b575f3****
)

Would anyone would have an idea of what is going wrong ?

Thanks in advance ! :-)