--- a/mercurial/util.py	Wed Nov 06 16:36:07 2013 -0600
+++ b/mercurial/util.py	Thu Nov 07 15:24:23 2013 -0600
@@ -1025,9 +1025,10 @@
     if t < 0:
         t = 0   # time.gmtime(lt) fails on Windows for lt < -43200
         tz = 0
-    if "%1" in format or "%2" in format:
+    if "%1" in format or "%2" in format or "%z" in format:
         sign = (tz > 0) and "-" or "+"
         minutes = abs(tz) // 60
+        format = format.replace("%z", "%1%2")
         format = format.replace("%1", "%c%02d" % (sign, minutes // 60))
         format = format.replace("%2", "%02d" % (minutes % 60))
     try:

--- a/tests/test-command-template.t	Wed Nov 06 16:36:07 2013 -0600
+++ b/tests/test-command-template.t	Thu Nov 07 15:24:23 2013 -0600
@@ -1445,7 +1445,7 @@
   $ hg ci -m h2e -d '4 0'
 
   $ hg merge -q
-  $ hg ci -m merge -d '5 0'
+  $ hg ci -m merge -d '5 -3600'
 
 No tag set:
 
@@ -1533,7 +1533,7 @@
   > EOF
 
   $ hg -R latesttag tip
-  test 10:dee8f28249af
+  test 10:9b4a630e5f5f
 
 Test recursive showlist template (issue1989):
 
@@ -1586,3 +1586,18 @@
   h1c
   b
   a
+
+Test date format:
+
+  $ hg log -R latesttag --template 'date: {date(date, "%y %m %d %S %z")}\n'
+  date: 70 01 01 10 +0000
+  date: 70 01 01 09 +0000
+  date: 70 01 01 08 +0000
+  date: 70 01 01 07 +0000
+  date: 70 01 01 06 +0000
+  date: 70 01 01 05 +0100
+  date: 70 01 01 04 +0000
+  date: 70 01 01 03 +0000
+  date: 70 01 01 02 +0000
+  date: 70 01 01 01 +0000
+  date: 70 01 01 00 +0000