SAML and Integration Server

I have a requirement as a consumer of an external webService using SAML.

According to the 8.2 Web Services Developer documentation, Integration Server supports SAML tokens only in policies attached to provider web service descriptors for inbound requests.

Can anyone explain how this can be resolved by only using the IS? I have heard about using Mediator, but I don’t think that will really help – although I am willing to take all suggestions.

Thanks in advance.