Connecting 2 Telephone lines

Hi All

I am trying to make a circuit that allow to connect one telephone line with other, in other words:

1.-On a Line 1 an incoming call is ringing,
2- next I hook off the this call
3- next I hook off the Line2 and wait for tone
3- Next connect Line1 with Line2, this way the caller can dial a second number with tones generated on his telephone.

And finally I have to return all to the initial state when the connection breaks.

Any idea, any help will be appreciate
Daniel