require "net/telnet"

t = Net::Telnet.new("Host" => "localhost", "Port" => 4242, "Prompt" => /repl> ¥z/n)
t.cmd ""

DATA.read.each do |l|
	t.cmd l do |s|
		puts s
	end
end

__END__
var prefs = Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefService);
prefs.setIntPref("network.proxy.type", 0);