tn_list.rb
 1form!
 2title "Choose Telephone Number"
 3instructions "Please choose one of the following numbers"
 4field(
 5	var: "tel",
 6	required: true,
 7	type: "list-single",
 8	label: "Telephone Number",
 9	options: @tns.map(&:option)
10)
11
12xml.set(xmlns: "http://jabber.org/protocol/rsm") do |xml|
13	xml.count @tns.length.to_s
14end