diff --git a/app/views/custom_fields/_form.html.erb b/app/views/custom_fields/_form.html.erb
index d8efca953..d09653b04 100644
--- a/app/views/custom_fields/_form.html.erb
+++ b/app/views/custom_fields/_form.html.erb
@@ -71,7 +71,7 @@ function toggle_custom_field_format() {
 <p><%= f.text_field :name, :required => true %></p>
 <p><%= f.select :field_format, custom_field_formats_for_select(@custom_field), {}, :onchange => "toggle_custom_field_format();",
                                                                     :disabled => !@custom_field.new_record? %></p>
-<p><%= f.check_box :multiple, :disabled => !@custom_field.new_record? %></p>
+<p><%= f.check_box :multiple, :disabled => @custom_field.multiple && !@custom_field.new_record? %></p>
 <p><label for="custom_field_min_length"><%=l(:label_min_max_length)%></label>
    <%= f.text_field :min_length, :size => 5, :no_label => true %> - 
    <%= f.text_field :max_length, :size => 5, :no_label => true %><br />(<%=l(:text_min_max_length_info)%>)</p>