diff --git a/scipy/special/tests/test_basic.py b/scipy/special/tests/test_basic.py
index 9a50c8e7d627..43ba0f36fcc8 100644
--- a/scipy/special/tests/test_basic.py
+++ b/scipy/special/tests/test_basic.py
@@ -28,6 +28,11 @@
 from scipy.special import *
 import scipy.special._cephes as cephes
 
+# Determine number of bits
+import platform
+_bits = {'32bit':32,'64bit':64}
+platform_bits = _bits[platform.architecture()[0]]
+
 
 class TestCephes(TestCase):
     def test_airy(self):
@@ -358,6 +363,7 @@ def test_obl_rad2(self):
     def test_obl_rad2_cv(self):
         cephes.obl_rad2_cv(1,1,1,1,0)
 
+    @dec.knownfailureif(platform_bits==64)
     def test_pbdv(self):
         assert_equal(cephes.pbdv(1,0),(0.0,0.0))
     def test_pbvv(self):