Aaaagh! the problem is back, and with the boy's machine too. He only gets kicked off whilst a page is loading, and has to redial. I either only get as far as my server, or sometimes I can't get that far. But often, everything works PERFECTLY.
As I said above, only the master jack is connected, and we are both using the same phone extension cable now, into the same jack, with only either computer plugged into it. A long cable snaking down the hall, not popular in certain quarters.
He got kicked off about 7 times last night, I took 5 goes to get on tonight. He tells me that he does sometimes get my problem.
Back to the drawing board.
I do wonder if it would be a good idea to have the computers on different virus-killers. The ETrust is due for renewel.

Well, at least we know (we hope we know) that it is a phone-wire or ISP problem (they say it isn't them) so an electrician pal is coming in next week to rewire right up to telecom's post, new two-wire system used here in NZ, different to the US system.

The washing machine broke down 2 weeks ago, not worth repairing, I lost a filling and had to go to to the dentist today, and the cooker stopped working tonight. I wonder if there's anything in paranoia?

On the other hand, I did fix the motor-mower, and the cooker should be not too much trouble. Mechanical, electrical, goooood! Electronic, bad. BAD!