Dylpickle

Hi Guys, I was wondering (I've been searching) how to join 2 lines together that have "middle" nodes. Say I've got a straight line with points A,B and C and another with 2 endpoints D and E. How do i go about joining the middle node (b) with the endpoint of the other line to make one unified "T" Piece? When i have tried selecting the correct nodes and "Join Curves" it connects the 2 lines end points and not the middle nose as I wish. Cheers http://puu.sh/tJHUr/11fb4c20ea.png (so connecting the bottom line node to the top lines middle)