Same here, I am ure it has been posted somewhere, as soon as I found a solution I will repost it here. 

hxxp: www. helpcenterlive. com/smf/installation_help_software_support/status_offline_even_when_im_online-t560. 0. html

Havent helped me, but it might be useful for others

This should work if not done earlier--,
Go to the assignments page and make sure that all of the Check boxes are checked for all of the assignments you want that operator to have.  Click edit and it will save the assigment as checked on and your online status should work.