diff --git a/tests/regressiontests/forms/models.py b/tests/regressiontests/forms/models.py
index f4f8607..0f55170 100644
--- a/tests/regressiontests/forms/models.py
+++ b/tests/regressiontests/forms/models.py
@@ -1,21 +1,40 @@
 from django.db import models
 
-class BoundaryModel(models.Model): 
+class BoundaryModel(models.Model):
     positive_integer = models.PositiveIntegerField(null=True, blank=True)
-    
+
+class ForeignKeyModel(models.Model):
+    foreign_key = models.ForeignKey('self', null=True, blank=True)
+
 __test__ = {'API_TESTS': """
 >>> from django.newforms import form_for_model
 
 # Boundary conditions on a PostitiveIntegerField #########################
->>> BoundaryForm = form_for_model(BoundaryModel) 
->>> f = BoundaryForm({'positive_integer':100}) 
->>> f.is_valid() 
+>>> BoundaryForm = form_for_model(BoundaryModel)
+>>> f = BoundaryForm({'positive_integer':100})
+>>> f.is_valid()
 True
->>> f = BoundaryForm({'positive_integer':0}) 
->>> f.is_valid() 
+>>> f = BoundaryForm({'positive_integer':0})
+>>> f.is_valid()
 True
->>> f = BoundaryForm({'positive_integer':-100}) 
->>> f.is_valid() 
+>>> f = BoundaryForm({'positive_integer':-100})
+>>> f.is_valid()
 False
 
-"""}
\ No newline at end of file
+>>> from django.newforms import form_for_instance
+>>> fk1 = ForeignKeyModel()
+>>> fk1.save()
+>>> fk2 = ForeignKeyModel(foreign_key=fk1)
+>>> fk2.save()
+>>> fk2.foreign_key == fk1
+True
+>>> Form = form_for_instance(fk1, formfield_callback=lambda f, initial: f.formfield(initial=initial))
+>>> f = Form()
+>>> f.is_valid()
+False
+>>> f = Form({'foreign_key': fk1.pk})
+>>> f.is_valid()
+True
+>>> f.errors
+{}
+"""}