Glad you got it working, though I'm still a bit confused. If this is a single-homed Linux box, the all-ones address should have worked. And reading /etc/hosts wouldn't tell it that your netmask was /25 as opposed to /8 or /24. So it'd be interesting to see what packets it's sending now that it works. It's almost as if it was successfully sending to the all-ones address, but saying "reply to 127.0.0.1" because that's what it thinks its IP address is, so the reply never went anywhere -- but in that case, Wireshark should have seen the outgoing packet.

Peter