I just replaced a 3-way switch, and when I was testing, I noticed that there
was 30 volts (Radio Shack analog meter) at the light socket when the
switches were off. I tried using one of the little idiot lights that glow
with voltage, and indeed, it glowed weakly. The light and the 2 3-way
switches work perfectly though. This circuit is fed by old knob and tube
wiring. Should I worry that something nasty is going on?

Thanks,
Michael