diff --git a/django/utils/numberformat.py b/django/utils/numberformat.py
index 069f49851b..9597cdd063 100644
--- a/django/utils/numberformat.py
+++ b/django/utils/numberformat.py
@@ -2,7 +2,7 @@ from django.conf import settings
 from django.utils.safestring import mark_safe
 
 
-def format(number, decimal_sep, decimal_pos, grouping=0, thousand_sep=''):
+def format(number, decimal_sep, decimal_pos=None, grouping=0, thousand_sep=''):
     """
     Gets a number (as a number or string), and returns it as a string,
     using formats definied as arguments:
@@ -29,11 +29,11 @@ def format(number, decimal_sep, decimal_pos, grouping=0, thousand_sep=''):
     # decimal part
     if '.' in str_number:
         int_part, dec_part = str_number.split('.')
-        if decimal_pos:
+        if decimal_pos is not None:
             dec_part = dec_part[:decimal_pos]
     else:
         int_part, dec_part = str_number, ''
-    if decimal_pos:
+    if decimal_pos is not None:
         dec_part = dec_part + ('0' * (decimal_pos - len(dec_part)))
     if dec_part: dec_part = decimal_sep + dec_part
     # grouping
diff --git a/tests/regressiontests/i18n/tests.py b/tests/regressiontests/i18n/tests.py
index c92823b9c7..2a7f0c2841 100644
--- a/tests/regressiontests/i18n/tests.py
+++ b/tests/regressiontests/i18n/tests.py
@@ -171,6 +171,7 @@ class FormattingTests(TestCase):
         settings.USE_THOUSAND_SEPARATOR = False
         self.assertEqual(u'66666.66', nformat(self.n, decimal_sep='.', decimal_pos=2, grouping=3, thousand_sep=','))
         self.assertEqual(u'66666A6', nformat(self.n, decimal_sep='A', decimal_pos=1, grouping=1, thousand_sep='B'))
+        self.assertEqual(u'66666', nformat(self.n, decimal_sep='X', decimal_pos=0, grouping=1, thousand_sep='Y'))
 
         settings.USE_THOUSAND_SEPARATOR = True
         self.assertEqual(u'66,666.66', nformat(self.n, decimal_sep='.', decimal_pos=2, grouping=3, thousand_sep=','))