diff --git a/System/Time.hsc b/System/Time.hsc
--- a/System/Time.hsc
+++ b/System/Time.hsc
@@ -184,7 +184,7 @@
 sec           0 .. 61           [Allows for two leap seconds]
 picosec       0 .. (10^12)-1    [This could be over-precise?]
 yday          0 .. 365          [364 in non-Leap years]
-tz       -43200 .. 43200        [Variation from UTC in seconds]
+tz       -43200 .. 50400        [Variation from UTC in seconds]
 \end{verbatim}
 -}
 
@@ -541,7 +541,7 @@
 
     if psec < 0 || psec > 999999999999 then
         error "Time.toClockTime: picoseconds out of range"
-    else if tz < -43200 || tz > 43200 then
+    else if tz < -43200 || tz > 50400 then
         error "Time.toClockTime: timezone offset out of range"
     else
       unsafePerformIO $ do
diff --git a/aclocal.m4 b/aclocal.m4
new file mode 100644
--- /dev/null
+++ b/aclocal.m4
@@ -0,0 +1,20 @@
+# FP_DECL_ALTZONE
+# ---------------
+# Defines HAVE_DECL_ALTZONE to 1 if declared, 0 otherwise.
+#
+# Used by base package.
+AC_DEFUN([FP_DECL_ALTZONE],
+[AC_REQUIRE([AC_HEADER_TIME])dnl
+AC_CHECK_HEADERS([sys/time.h])
+AC_CHECK_DECLS([altzone], [], [],[#if TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# if HAVE_SYS_TIME_H
+#  include <sys/time.h>
+# else
+#  include <time.h>
+# endif
+#endif])
+])# FP_DECL_ALTZONE
+
diff --git a/old-time.cabal b/old-time.cabal
--- a/old-time.cabal
+++ b/old-time.cabal
@@ -1,5 +1,5 @@
 name:		old-time
-version:	1.0.0.3
+version:	1.0.0.4
 license:	BSD3
 license-file:	LICENSE
 maintainer:	libraries@haskell.org
@@ -11,6 +11,7 @@
     For new code, the new time library is recommended.
 build-type: Configure
 extra-source-files:
+        aclocal.m4
         config.guess config.sub install-sh
         configure.ac configure
         include/HsTimeConfig.h.in