diff --git a/lib/formtastic/helpers/buttons_helper.rb b/lib/formtastic/helpers/buttons_helper.rb
index 89d017bc1..55df22c28 100644
--- a/lib/formtastic/helpers/buttons_helper.rb
+++ b/lib/formtastic/helpers/buttons_helper.rb
@@ -246,6 +246,7 @@ def commit_button(*args)
                 Formtastic::I18n.t(commit_button_i18n_key, :model => commit_button_object_name)) unless text.is_a?(::String)
 
         button_html = options.delete(:button_html) || {}
+        button_html[:id] ||= "#{@object_name}_submit"
         button_html.merge!(:class => [button_html[:class], commit_button_i18n_key].compact.join(' '))
 
         wrapper_html = options.delete(:wrapper_html) || {}
@@ -253,7 +254,7 @@ def commit_button(*args)
 
         accesskey = (options.delete(:accesskey) || default_commit_button_accesskey) unless button_html.has_key?(:accesskey)
         button_html = button_html.merge(:accesskey => accesskey) if accesskey
-        
+
         template.content_tag(:li, Formtastic::Util.html_safe(submit(text, button_html)), wrapper_html)
       end
 
@@ -274,10 +275,10 @@ def commit_button_object_name
         else
           object_name = @object_name.to_s.send(label_str_method)
         end
-        
+
         object_name
       end
-      
+
       def commit_button_i18n_key
         if new_or_persisted_object?
           key = @object.persisted? ? :update : :create
@@ -291,11 +292,11 @@ def commit_button_i18n_key
       def commit_button_wrapper_html_class
         ['commit', 'button'] # TODO: Add class reflecting on form action.
       end
-      
+
       def new_or_persisted_object?
         @object && (@object.respond_to?(:persisted?) || @object.respond_to?(:new_record?))
       end
-      
+
     end
   end
 end
\ No newline at end of file
diff --git a/spec/helpers/commit_button_helper_spec.rb b/spec/helpers/commit_button_helper_spec.rb
index a8d9d2ba9..eba019b72 100644
--- a/spec/helpers/commit_button_helper_spec.rb
+++ b/spec/helpers/commit_button_helper_spec.rb
@@ -29,7 +29,7 @@
     end
 
   end
-  
+
   describe 'when not persisted' do
 
     before do
@@ -44,12 +44,12 @@
           concat(builder.commit_button)
         end)
       end
-      
+
       output_buffer.should have_tag('.commit input[@value="Submit Post"]')
     end
   end
-  
-  
+
+
   describe 'when used on any record' do
 
     before do
@@ -62,7 +62,7 @@
     it 'should render a commit li' do
       output_buffer.should have_tag('li.commit')
     end
-    
+
     it 'should render a button li' do
       output_buffer.should have_tag('li.button')
     end
@@ -204,11 +204,11 @@
                   }
                }
          end
-         
+
          after do
            ::I18n.backend.reload!
          end
-         
+
          it 'should render an input with localized label (I18n)' do
            with_config :i18n_lookups_by_default, true do
              ::I18n.backend.store_translations :en,
@@ -225,7 +225,7 @@
              output_buffer.should have_tag(%Q{li.commit input[@value="Custom Submit Post"][@class~="submit"]})
            end
          end
-         
+
          it 'should render an input with anoptional localized label (I18n) - if first is not set' do
            with_config :i18n_lookups_by_default, true do
              concat(semantic_form_for(:post, :url => 'http://example.com') do |builder|
@@ -427,7 +427,7 @@ def self.human_name
     end
 
   end
-  
+
   describe ':wrapper_html option' do
 
     describe 'when provided' do
@@ -457,14 +457,21 @@ def self.human_name
     end
 
     describe 'when not provided' do
-      it 'should use default id and class' do
+      it 'should use default class' do
         concat(semantic_form_for(@new_post) do |builder|
           concat(builder.commit_button('text'))
         end)
         output_buffer.should have_tag("form li.commit.button")
       end
+
+      it 'should use default id' do
+        concat(semantic_form_for(@new_post) do |builder|
+          concat(builder.commit_button('text'))
+        end)
+        output_buffer.should have_tag("form li.commit.button input#post_submit")
+      end
     end
 
   end
-  
+
 end