My current setup is as follows:
I have 2 lines coming into the home. There are 2 jacks in the bedroom, 1 for each line. Jack 1 (line 1) has the red and green wires attached to the screws. The yellow and black wires seem to be connected to the back of jack 2 (line 2). Jack 2 has the red and green attached to the screws. Jack 1 is connected by a cable to the main box in the closet.
I also have a jack 3 (with line 2) at my computer. That jack is attached to a separate cable than Jack 1 is attached to and starts from the same box in the closet as Jack 1 starts. My ADSL connection is attached to jack 3.
What I want to do, without having to pay $200 for the telco to do it, is have a jack 4 at my computer with line 1. I opened the jack 3 and noticed that the red and green wires are attached to the screws, and the yellow and black wires are connected to the ADSL box right next to jack 3. My guess from the reading I've done is that I cannot use the jack 3 wiring to get a connection to line 1 (as I have in my bedroom) since the ADSL connection is using the yeloow/black set of wires. Hopefully, I gave enough of a description that somebody can confirm this and possibly offer alternatives?
One other thing, the ADSL connection with jack 3 was made a year or two after the 3 jacks were initially installed.
Barry