diff --git a/django/contrib/formtools/preview.py b/django/contrib/formtools/preview.py
index c56fdff..75bc8e2 100644
--- a/django/contrib/formtools/preview.py
+++ b/django/contrib/formtools/preview.py
@@ -6,6 +6,7 @@ import cPickle as pickle
 
 from django.conf import settings
 from django.http import Http404
+from django.forms import BooleanField
 from django.shortcuts import render_to_response
 from django.template.context import RequestContext
 from django.utils.hashcompat import md5_constructor
@@ -106,7 +107,18 @@ class FormPreview(object):
         Subclasses may want to take into account request-specific information
         such as the IP address.
         """
-        data = [(bf.name, bf.data or '') for bf in form] + [settings.SECRET_KEY]
+        # Ensure that the hash does not change when a BooleanField's bound 
+        # data is a string `False' or a boolean False.
+        # DRY: Rather than re-coding this special behaviour here, we 
+        # create a dummy BooleanField and call its clean method to get a 
+        # boolean True or False verdict that is consistent with 
+        # BooleanField.clean()
+        dummy_bool = BooleanField(required=False)
+        def _cleaned_data(bf):
+            if isinstance(bf.field, BooleanField):
+                return dummy_bool.clean(bf.data)
+            return bf.data
+        data = [(bf.name, _cleaned_data(bf) or '') for bf in form] + [settings.SECRET_KEY]
         # Use HIGHEST_PROTOCOL because it's the most efficient. It requires
         # Python 2.3, but Django requires 2.3 anyway, so that's OK.
         pickled = pickle.dumps(data, pickle.HIGHEST_PROTOCOL)
diff --git a/django/contrib/formtools/tests.py b/django/contrib/formtools/tests.py
index 2ea0cc9..1a5182a 100644
--- a/django/contrib/formtools/tests.py
+++ b/django/contrib/formtools/tests.py
@@ -4,8 +4,6 @@ from django import http
 from django.test import TestCase
 
 success_string = "Done was called!"
-test_data = {'field1': u'foo',
-             'field1_': u'asdf'}
 
 
 class TestFormPreview(preview.FormPreview):
@@ -17,6 +15,7 @@ class TestFormPreview(preview.FormPreview):
 class TestForm(forms.Form):
     field1 = forms.CharField()
     field1_ = forms.CharField()
+    bool1 = forms.BooleanField(required=False)
 
 
 class PreviewTests(TestCase):
@@ -27,6 +26,7 @@ class PreviewTests(TestCase):
         self.preview = preview.FormPreview(TestForm)
         input_template = '<input type="hidden" name="%s" value="%s" />'
         self.input = input_template % (self.preview.unused_name('stage'), "%d")
+        self.test_data = {'field1':u'foo', 'field1_':u'asdf'}
 
     def test_unused_name(self):
         """
@@ -59,8 +59,8 @@ class PreviewTests(TestCase):
         """
         # Pass strings for form submittal and add stage variable to
         # show we previously saw first stage of the form.
-        test_data.update({'stage': 1})
-        response = self.client.post('/test1/', test_data)
+        self.test_data.update({'stage': 1})
+        response = self.client.post('/test1/', self.test_data)
         # Check to confirm stage is set to 2 in output form.
         stage = self.input % 2
         self.assertContains(response, stage, 1)
@@ -77,11 +77,30 @@ class PreviewTests(TestCase):
         """
         # Pass strings for form submittal and add stage variable to
         # show we previously saw first stage of the form.
-        test_data.update({'stage': 2})
-        response = self.client.post('/test1/', test_data)
+        self.test_data.update({'stage':2})
+        response = self.client.post('/test1/', self.test_data)
         self.failIfEqual(response.content, success_string)
-        hash = self.preview.security_hash(None, TestForm(test_data))
-        test_data.update({'hash': hash})
-        response = self.client.post('/test1/', test_data)
+        hash = self.preview.security_hash(None, TestForm(self.test_data))
+        self.test_data.update({'hash': hash})
+        response = self.client.post('/test1/', self.test_data)
+        self.assertEqual(response.content, success_string)
+
+    def test_bool_submit(self):
+        """
+        Test contrib.formtools.preview form submittal when form contains:
+        BooleanField(required=False)
+
+        Ticket: #6209 - When an unchecked BooleanField is previewed, the preview
+        form's hash would be computed with no value for ``bool1``. However, when
+        the preview form is rendered, the unchecked hidden BooleanField would be 
+        rendered with the string value 'False'. So when the preview form is
+        resubmitted, the hash would be computed with the value 'False' for
+        ``bool1``. We need to make sure the hashes are the same in both cases.
+
+        """
+        self.test_data.update({'stage':2})
+        hash = self.preview.security_hash(None, TestForm(self.test_data))
+        self.test_data.update({'hash':hash, 'bool1':u'False'})
+        response = self.client.post('/test1/', self.test_data)
         self.assertEqual(response.content, success_string)