How to make Sametime 12 Meetings work on Android

With the customer where I installed Sametime 12 we had an issue with Meetings using an Android device. From a Android phone a user could not join a meeting or create a new one. With iOS devices, this problem did not happen. We tested on Sametime 12.0.FP1 and Sametime 12.0.1

We opened a Case and in the end HCL Support found the solution, you have to add to the file .env this line

STCONF_TOKENDOMAIN=yoursametimeserver.yourdomain.com