Hi Gavin,
Have a look at teh following Documentation to to see if they can help you
Configuration of trusted identity provider :
http://help.sap.com/saphelp_nw74/helpdata/en/7e/80a762e8b4441fb53b1f6d9bde4f4d/frameset.htm
setting up OATH2.0 client :
http://help.sap.com/saphelp_nw74/helpdata/en/de/d106c66334432f963715cb0dc3165f/content.htm
parameter of OATH2.0
http://help.sap.com/saphelp_nw74/helpdata/en/d7/d0a4620b694bf499ea3bf78d117bd8/content.htm
OATH2.0 configuration :
http://help.sap.com/saphelp_nw74/helpdata/en/1e/c60c33be784846aad62716b4
a1df39/content.htm?frameset=/en/1e/c60c33be784846aad62716b4a1df39/frameset.htm
Regards,
David