I'm expanding the phone/data network at my church and have two CAT5 wires ran from my network closet to some new offices. One cable will go into a switch and then out to all the computers; that part is easy. But I'm wondering if there's a way that I can do something similar for the phones.

There are 8 wires inside a CAT5 cable, and a phone only needs to use 2, right? So, theoretically I can just use 2 wires for each line and have 4 phone lines, right? Each pair will be punched into a patch panel that runs into our PBX on one end, and then into another patch panel in the new area, with cat2 phone cables going to the phones from there.

Does it matter which colors are used, as long as they match on both ends? Each pair should be punched into slots 4 and 5 on the panels, right?

Is there anything I'm missing or need to consider?

Thanks,
Ian