Session Creation Error: Invalid credential

Despite the IdP has been configured properly such that its /SSO being protected by appropriate mechanism and you're successfully authenticated, but the IdP will still throw this error.

The log will show something similar to:

ERROR [IdP] - Encountered an error during validation: java.security.NoSuchAlgorithmException: PKIX
ERROR [IdP] - Supplied TLS credential (C=AU,ST=NSW,L=Sydney,O=Macquarie University,OU=xxx) is
NOT valid for provider (urn:mace:federation.org.au:testfed:level-1:xxx), to whom this artifact
was issued.
ERROR [IdP] - Error while processing request: org.opensaml.SAMLException: Invalid credential.

The reason for this is because you're using a wrong java version.

Specifically, tomcat by default uses as JAVA_HOME /usr/lib/jvm/java, which is a symlink to /etc/alternatives/java_sdk. You need to either edit /ets/sysconfig/tomcat5 or change this symlink with /etc/alternatives, or a vanilla installation of Sun java.

When tomcat5 runs under GJC, the IdP appears to run fine, however it is not able to verify PKI credentials of Service Providers requesting attributes (Artifact profile), hence you will see the authentication request to fail on the log.
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