Assign multiple lines to one phone

RC should allow for assigning multiple lines to one phone. If there is one assistant, and they are working for multiple people, the assistant should be able to tell what calls were missed by what person. This is currently not possible. This feature would lead to a great improvement in business environments where the secretary needs to monitor multiple lines. Currently we can only forward lines from the bosses to the secretary, but this doesn't solve the issue. Neither does the Presence feature.