Need to add the following known issue to the 7.1 release notes:

If you are using SAML adapters with the isPassive option set to "true", there is a known issue that prevents correct handling of the SAML response. To prevent this issue from occurring, you must upgrade both RH-SSO server and the SAML adapter.

For more info see https://issues.jboss.org/browse/RHSSO-839 (adding same info to Upgrading Guide)