Check out voip.ms and see if you can have CF-Busy and CF-No Answer to different locations. Then you set the destination of line 1 to line 2 and line 2 to line 3 on busy and VM for the destination of all 3 lines on no answer.

Sometimes, they try to save you and not allow the 2nd hop, so you need to test to make sure that you can ring 1 then 2 then 3. It may die after the first forward :-)


Carl