diff --git a/python-biopython.spec b/python-biopython.spec
index 4651e55..b27c30e 100644
--- a/python-biopython.spec
+++ b/python-biopython.spec
@@ -3,7 +3,7 @@
 
 Name:             python-biopython
 Version:          1.43
-Release:          2%{?dist}
+Release:          3%{?dist}
 Summary:          Python tools for computational molecular biology
 Source0:          http://biopython.org/DIST/biopython-%{version}.tar.gz
 Patch0:           biopython-setup_test.patch
@@ -64,14 +64,17 @@ rm -rf $RPM_BUILD_ROOT
 %defattr(-,root,root,-)
 %doc Doc Scripts
 %doc CONTRIB DEPRECATED LICENSE NEWS README
-%dir %{python_sitelib}/Bio
-%{python_sitelib}/Bio/*
-%dir %{python_sitelib}/Martel
-%{python_sitelib}/Martel/*
-%dir %{python_sitelib}/BioSQL
-%{python_sitelib}/BioSQL/*
+%dir %{python_sitearch}/Bio
+%{python_sitearch}/Bio/*
+%dir %{python_sitearch}/Martel
+%{python_sitearch}/Martel/*
+%dir %{python_sitearch}/BioSQL
+%{python_sitearch}/BioSQL/*
 
 %changelog
+* Mon Apr 17 2007 Alex Lancaster <alexl@users.sourceforge.net> 1.43-3
+- Use python_sitearch macro to enable x86_64 builds work.
+
 * Mon Apr 16 2007 Alex Lancaster <alexl@users.sourceforge.net> 1.43-2
 - Fix Source0 URL as per suggestion from Parag AN on #235989.