Authentication issue after upgrading to shibboleth-2.5.0-2.1 service provider software

[John Lee]

Hi,

We have the Shibboleth Service Provider software running on a RHEL6 box, which is how users are authenticated to use our web apps.
After performing a regular yum update to upgrade to the latest: shibboleth-2.5.0-2.1, it is no longer possible to login to our web apps.
On-screen message is:
--------------
ERROR
An error occurred while processing your request. Please contact your helpdesk or user ID office for assistance.
This service requires cookies. Please ensure that they are enabled and try your going back to your desired resource and trying to login again.
Use of your browser's back button may cause specific errors that can be resolved by going back to your desired resource and trying to login again.
If you think you were sent here in error, please contact technical support
Error Message: Message did not meet security requirements
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Have there been any reports of a similar problem, or any suggestions of what the problem might be.
I've looked in the following log file and have not found anything obvious:
/var/log/shibboleth/shibd.log

If I downgrade to our original version of the service provider software: shibboleth-2.4.3, authentication is fine again.

Regards,
John

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