We have 2 users sources (for 2 domains (DOMAIN1 where my primary server is
and DOMAIN2 no ZCM server) with a trust between those domains).

When I am at DOMAIN2 location, at logon, ZCM ask for my username and
password. If I give the DOMAIN2\username and password with the local realm,
login fails. If I give DOMAIN1\username - password, login works. Why ?

Anybody can help me with this ?