Multitenant with CAS-LDAP

[bpaume.ext]

Hi all,
We are using and testing a multitenant version of Ofbiz/Tercompta with purpose 
ldap (coupled with CAS).
When ldap purpose is not used, we are able to choose a tenant in GUI during 
login.
But with ldap/cas there is no GUI!
How can we set correct tenantId ?  what is best procedure to follow ? modify 
classes in package org.ofbiz.webapp.control?  Customize a LoginWorker for 
instance?
 
Thanks