Can I create a chat room for 3 different clients for Gtalk service?
In Adium:


Right click on one of the contacts, and use "Initiate Multiuser Chat with (name)@gmail.com"
You should now join a group chat yourself, and an invitation will be send to that contact.
Right click on the other contact, and select "Invite to Chat" → (The name of the private chat you created).
Now the other contact gets an invitation they should accept.