After a few calls to the service line, the answer isn’t logical, but it works.
You'll need a valid USERTrust primary root certificate in Privacy-Enhanced Mail (PEM) format to validate the IU Secure connection.
Signature validity is determined by checking the authenticity of the signature’s digital ID certificate status and document integrity: In Acrobat or Reader, the signature of a certified or signed document is valid if you and the signer have a trust relationship.
The trust level of the certificate indicates the actions for which you trust the signer.
Home Edition, etc.): You have now succesfully configured Windows XP to connect to eduroam network.
In order to connect to eduroam network in future, simply bring up Wireless Network Connection window by double-clicking its icon in the tray bar , select eduroam network and click on Connect.