|As far as the condo unit goes, the only line coming in--that has already demonstrated the ability to carry DSL--is a CAT5 cable with RJ45 connector. To be absolutely clear, there are no (traditional) phone line cables with RJ11 connectors.|
We use Cat5e extensively for telephone here where I work. Since a phone line only uses 2 wires and a Cat5e has 8, that means you can run up to 4 phones out of a single cable.
We also use them with RJ-45's in some instances and the same applies, of the 8 wires, you're only using one pair.
This leaves only one question, does your DSL modem have an RJ-45 connector on the "in" side of it. As I pointed out earlier, everyone I've ever seen, the "out" port was definitely RJ-45.
I hesitate to contact the ISP or phone company...
I hear ya! But, I really think you're going to have to talk to somebody to get the DSL modem hooked up to the phone line so you can get the DSL working.