I replicated a pentaho installation on new virtual machines (1 Tomcat server with pentaho 5.2 and 1 postgresql 9.3, exactly the same OS...).

Everything works, we can login, work, etc... except admin UI who can get XML response of the user list, it's an empty XML list... the API URL call by UI is : https://domain.name/pentaho/api/userroledao/users
Can you help me to find the next step to resolve the problem ? Thanks

Pic of XML API result call by admin UI :