Index: tests/regressiontests/comment_tests/fixtures/comment_tests.json
===================================================================
--- tests/regressiontests/comment_tests/fixtures/comment_tests.json	(revision 12738)
+++ tests/regressiontests/comment_tests/fixtures/comment_tests.json	(working copy)
@@ -1,5 +1,12 @@
 [
   {
+    "model" : "comment_tests.book",
+    "pk" : 1,
+    "fields" : {
+        "dewey_decimal" : "12.34"
+    }
+  },
+  {
     "model" : "comment_tests.author",
     "pk" : 1,
     "fields" : {
Index: tests/regressiontests/comment_tests/models.py
===================================================================
--- tests/regressiontests/comment_tests/models.py	(revision 12738)
+++ tests/regressiontests/comment_tests/models.py	(working copy)
@@ -28,3 +28,7 @@
 
     def __str__(self):
         return self.title
+
+class Book(models.Model):
+    dewey_decimal = models.DecimalField(primary_key = True, decimal_places=2, max_digits=5)
+    
\ No newline at end of file
Index: tests/regressiontests/comment_tests/tests/comment_view_tests.py
===================================================================
--- tests/regressiontests/comment_tests/tests/comment_view_tests.py	(revision 12738)
+++ tests/regressiontests/comment_tests/tests/comment_view_tests.py	(working copy)
@@ -3,12 +3,20 @@
 from django.contrib.auth.models import User
 from django.contrib.comments import signals
 from django.contrib.comments.models import Comment
-from regressiontests.comment_tests.models import Article
+from regressiontests.comment_tests.models import Article, Book
 from regressiontests.comment_tests.tests import CommentTestCase
 
 post_redirect_re = re.compile(r'^http://testserver/posted/\?c=(?P<pk>\d+$)')
 
 class CommentViewTests(CommentTestCase):
+    def testBook(self):
+        b = Book.objects.get(pk='12.34')
+        data = self.getValidData(b)
+        data["comment"] = "This is another comment"
+        data["object_pk"] = 'cookies'
+        response = self.client.post("/post/", data)
+        self.assertEqual(response.status_code, 405)
+        self.assertEqual(response["Allow"], "POST")
 
     def testPostCommentHTTPMethods(self):
         a = Article.objects.get(pk=1)
@@ -234,3 +242,4 @@
         broken_location = location + u"\ufffd"
         response = self.client.get(broken_location)
         self.assertEqual(response.status_code, 200)
+