Raoul,
I am very surprised that nobody has responded to your message yet. I thought it was quite interesting, and I am particularly keen to hear more about why you feel Kerberos cannot be used. You mentioned that you were concerned about the upgrades required. Is that the only reason ? I also wondered if you have searched on the SAP Store for other SSO products that support Kerberos to see if they also have the same upgrade requirements ?
Thanks,
Tim