|The item I was thinking about in # 2 above was a Duofone (radio shack) 'Two-Line Controller with Hold", catalog # 43-239 but they no longer carry it.|
I came across this 2-line phone while looking for the controller on ebay:
I assume you have 2 single lines--2 RJ11 lines. The 2-line phone uses an RJ14 line. They're exactly the same in that they both have 4-wires. Of those a single line phone only needs 2 wires. So in an RJ14 two of the wires are for one line and two are for the second line. You'll need an adapter to connect the 2 RJ11's to make an RJ14.
Real men don't use AntiVirus; they just reformat