<% custom_field_values = @issue.editable_custom_field_values %>
<% i = 0 %> <% split_on = (custom_field_values.size / 2.0).ceil - 1 %> <% custom_field_values.each do |value| %>

<%= custom_field_tag_with_label :issue, value, :required => @issue.required_attribute?(value.custom_field_id) %>

<% if i == split_on -%>
<% end -%> <% i += 1 -%> <% end -%>