<% address_id = address_type.chars.first %>

<% ADDRESS_FIELDS.each do |field| %>
  <% if field == "country" %>
    <p class="form-group" id="<%= "#{address_id}country" %>">
      <%= address_form.label :country_id, Spree.t(:country) %><span class="required">*</span><br />
      <span id="<%= "#{address_id}country-selection" %>">
        <%= address_form.collection_select :country_id, available_countries, :id, :name, {}, {:class => 'required'} %>
      </span>
    </p>
  <% elsif field == "state" %>
    <%= address_field(address_form, :state, address_id) { address_state(address_form, address.country, address_id) } if Spree::Config[:address_requires_state] %>
  <% else %>
    <% next if field == "company" && !Spree::Config[:company] %>
    <% next if field == "alternative_#{address_id}_phone" && !Spree::Config["alternative_#{address_id}_phone"] %>
    <%= address_field(address_form, field.to_sym, address_id) %>
  <% end %>
<% end %>
<% address_id = address_type.chars.first %>

<% ADDRESS_FIELDS.each do |field| %>
  <% if field == "country" %>
    <p class="form-group" id="<%= "#{address_id}country" %>">
      <%= address_form.label :country_id, Spree.t(:country) %><span class="required">*</span><br />
      <span id="<%= "#{address_id}country-selection" %>">
        <%= address_form.collection_select :country_id, available_countries, :id, :name, {}, {:class => 'required form-control'} %>
      </span>
    </p>
  <% elsif field == "state" %>
    <%= address_field(address_form, :state, address_id) { address_state(address_form, address.country, address_id) } if Spree::Config[:address_requires_state] %>
  <% else %>
    <% next if field == "company" && !Spree::Config[:company] %>
    <% next if field == "alternative_#{address_id}_phone" && !Spree::Config["alternative_#{address_id}_phone"] %>
    <%= address_field(address_form, field.to_sym, address_id) %>
  <% end %>
<% end %>

Adjust country select for bootstrap
Adjust country select for bootstrap

This adds the bootstrap styling to the country select box in the address forms. Goodlooking!
