Sametime Chat Verse | iNotes integration stops working after upgrade to 11.5

I updated a customer Sametime server from 11.0 to 11.5 and the integration of iNotes and Verse on Premises with Sametime stopped working.
I asked if anyone has seen this happen and my fellow HCL Ambassador Mathieu Fabien pointed me to a HCL technote, here, that explain what the problem is due to and gives the solution.