diff --git a/dkim/__init__.py b/dkim/__init__.py
index 36d6fb0..3c225f2 100644
--- a/dkim/__init__.py
+++ b/dkim/__init__.py
@@ -171,14 +171,26 @@ def validate_signature_fields(sig):
             "l= value is not a decimal integer (%s)" % sig[b'l'])
     if b'q' in sig and sig[b'q'] != b"dns/txt":
         raise ValidationError("q= value is not dns/txt (%s)" % sig[b'q'])
-    if b't' in sig and re.match(br"\d+$", sig[b't']) is None:
-        raise ValidationError(
-            "t= value is not a decimal integer (%s)" % sig[b't'])
+    now = int(time.time())
+    slop = 36000		# 10H leeway for mailers with inaccurate clocks
+    t_sign = 0
+    if b't' in sig 
+        if re.match(br"\d+$", sig[b't']) is None:
+	    raise ValidationError(
+		"t= value is not a decimal integer (%s)" % sig[b't'])
+	t_sign = int(sig[b't'])
+	if t_sign > now + slop:
+	    raise ValidationError(
+		"t= value is in the future (%s)" % sig[b't'])
     if b'x' in sig:
         if re.match(br"\d+$", sig[b'x']) is None:
             raise ValidationError(
                 "x= value is not a decimal integer (%s)" % sig[b'x'])
-        if int(sig[b'x']) < int(sig[b't']):
+	x_sign = int(sig[b'x'])
+	if x_sign < now - slop:
+	    raise ValidationError(
+		"x= value is past (%s)" % sig[b'x'])
+        if x_sign < t_sign:
             raise ValidationError(
                 "x= value is less than t= value (x=%s t=%s)" %
                 (sig[b'x'], sig[b't']))
diff --git a/packaging/pydkim.spec b/packaging/pydkim.spec
index 52d9a9b..f749c66 100644
--- a/packaging/pydkim.spec
+++ b/packaging/pydkim.spec
@@ -1,11 +1,12 @@
 %define __python python2.6
-%define pythonbase python26
+%define pythonbase python
 
 Summary: Python DKIM library
 Name: %{pythonbase}-pydkim
-Version: 0.5.3
+Version: 0.5.4
 Release: 1
 Source0: http://hewgill.com/pydkim/pydkim-%{version}.tar.bz2
+Patch: pydkim.patch
 License: BSD-like
 Group: Development/Libraries
 BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-buildroot
@@ -27,9 +28,10 @@ Python DKIM library
 %{__python} setup.py build
 
 %install
+rm -rf $RPM_BUILD_ROOT
 %{__python} setup.py install --root=$RPM_BUILD_ROOT --record=INSTALLED_FILES
 sed -i -e'/man1/d' INSTALLED_FILES
-#grep '\.pyc$' INSTALLED_FILE | sed -e's/c$/o/' >>INSTALLED_FILES
+#grep '\.pyc$' INSTALLED_FILES | sed -e's/c$/o/' >>INSTALLED_FILES
 mkdir -p ${RPM_BUILD_ROOT}%{_mandir}/man1
 cp -p man/*.1 ${RPM_BUILD_ROOT}%{_mandir}/man1
 
@@ -41,7 +43,7 @@ rm -rf $RPM_BUILD_ROOT
 %doc ChangeLog README LICENSE TODO
 %{_mandir}/man1/dkimsign.1.gz
 %{_mandir}/man1/dkimverify.1.gz
-/usr/lib/%{__python}/site-packages/dkim/__main__.pyo
+#/usr/lib/%{__python}/site-packages/dkim/__main__.pyo
 
 %changelog
 * Sat Apr 21 2012 Stuart Gathman <stuart@bmsi.com> 0.5.3-1