Robert,

I think that yes, different groups is what I need. I have JUST discovered a section (19.1) with title "Multi Group" in the manual that describes PRECISELY what to do for this type of setup!

I proceeded as I told you. Now the different groups seem to be working correctly. Users assigned to a group see only the queues for this group and not the others, so its perfect. However, I have detected a new problem. I don't know whether this happened before the inclusion of the mutually exclusive groups or is a new problem. Here it is: Let's suppose that a customer creates a new ticket for some queue. Then, sooner or later the person in charge of this queue will see the ticket. Suppose again that this person wants to send back a comment to the customer and decides to compose an answer (using the appropriate link in the ticket's area within the queue's window). You are driven to the "Compose answer" page. Well, the person composes the answer, including, for instance, the new state of the ticket and some words explaining what to do... Then, sends the answer. Well, here is where the problem appears: instead of adding the new followup to the ticket, I get AGAIN AND AGAIN the "Compose answer" page (and the ticket is LOCKED). The only think I can do i press "back" in my browser as many times as necessary (depending on how many times I pressed the send button) and, when reaching again the queue page, unlock the ticket. Curiously, the Phone followup works well. That is, if we suppose that the customer phoned the person in charge and a followup is added using this option, the ticket is updated successfully (that is, it is shown in the ticket's history). I've been looking at the logs and found nothing pointing to a problem. The only weird thing I noticed is that at the very beginning of the "Compose answer" page there are a red warning stating that the email address is not correct because of an invalid FQDN. However, SMTP emailing is working very fine with all the other options. Any ideas? Thanks alot for this long run help! And again, congratulations for OTRS! Jose.