SAML module SP config error

Hi all,

I am implementing the SAML2 module in a Mendix 5.16.1 application. I did this before and never had a problem, but now, even though I use the exact same module and exact same Mendix version (5.16.1), I am getting a Java-error while saving the SP data, stating:

com.mendix.systemwideinterfaces.MendixRuntimeException: java.security.AccessControlException: access denied ("java.util.PropertyPermission""org.w3c.dom.DOMImplementationSourceList""read")
    at SAML20.MB_SaveSPMetadata (JavaAction : 'ReloadConfiguration')

So; it seems that the proper 'ALLOW' for this org.w3c.dom.DOMImplementationSourceList Class is missing. This is indeed the case if I look at the security.policy file, but I can't find a way to fix it.

Any ideas anybody?