diff --git a/src/backend/utils/adt/nabstime.c b/src/backend/utils/adt/nabstime.c
index 434b5c95a83932c846d5afffbfc423b977093787..31117389b0a991e25a92f08ec91167b3ec13ad06 100644
--- a/src/backend/utils/adt/nabstime.c
+++ b/src/backend/utils/adt/nabstime.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/nabstime.c,v 1.80 2001/01/24 19:43:14 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/nabstime.c,v 1.81 2001/02/13 14:32:52 momjian Exp $
  *
  * NOTES
  *
@@ -205,7 +205,17 @@ abstime2tm(AbsoluteTime _time, int *tzp, struct tm * tm, char *tzn)
 
 #if defined(HAVE_TM_ZONE) || defined(HAVE_INT_TIMEZONE)
 	if (tzp != NULL)
+	{
 		tx = localtime((time_t *) &time);
+# ifdef NO_MKTIME_BEFORE_1970
+		if (tx->tm_year < 70 && tx->tm_isdst == 1)
+		{
+			time -= 3600;
+			tx = localtime((time_t *) &time);
+			tx->tm_isdst = 0;
+		}
+# endif
+	}
 	else
 	{
 		tx = gmtime((time_t *) &time);
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index e3facb7f1e48ca9d43dc29a4ac3899b3489c2ce6..a01a790124f996d46af47a4b9da7bbb13cc7f099 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.44 2001/01/24 19:43:14 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v 1.45 2001/02/13 14:32:52 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -315,6 +315,14 @@ timestamp2tm(Timestamp dt, int *tzp, struct tm * tm, double *fsec, char **tzn)
 
 #if defined(HAVE_TM_ZONE) || defined(HAVE_INT_TIMEZONE)
 			tx = localtime(&utime);
+# ifdef NO_MKTIME_BEFORE_1970
+			if (tx->tm_year < 70 && tx->tm_isdst == 1)
+			{
+				utime -= 3600;
+				tx = localtime(&utime);
+				tx->tm_isdst = 0;
+			}
+# endif
 			tm->tm_year = tx->tm_year + 1900;
 			tm->tm_mon = tx->tm_mon + 1;
 			tm->tm_mday = tx->tm_mday;
diff --git a/src/include/port/aix.h b/src/include/port/aix.h
index 782d84bb9134be6a7ac9d87799eca3b8111b54bb..5e4f70a7900bb561c6b838dda3a351a800fee5f0 100644
--- a/src/include/port/aix.h
+++ b/src/include/port/aix.h
@@ -1,6 +1,7 @@
 #define CLASS_CONFLICT
 #define DISABLE_XOPEN_NLS
 #define HAS_TEST_AND_SET
+#define NO_MKTIME_BEFORE_1970
 typedef unsigned int slock_t;
 
 #include <sys/machine.h>		/* ENDIAN definitions for network
diff --git a/src/include/port/irix5.h b/src/include/port/irix5.h
index 668796004966f1b0294c3cb3633ac1f6b87db9f7..ff91fc29227f6b2264964c1c456b9e342ec41c68 100644
--- a/src/include/port/irix5.h
+++ b/src/include/port/irix5.h
@@ -1,2 +1,3 @@
 #define HAS_TEST_AND_SET
+#define NO_MKTIME_BEFORE_1970
 typedef unsigned long slock_t;
diff --git a/src/test/regress/resultmap b/src/test/regress/resultmap
index c8f0a4302ca7aa4a9d34b4d472638930acbc54f4..417412d37f5231ec4bc94d46db16a4a659ecfb58 100644
--- a/src/test/regress/resultmap
+++ b/src/test/regress/resultmap
@@ -1,5 +1,3 @@
-abstime/.*-aix4=abstime-1947-PDT
-abstime/.*-irix6=abstime-1947-PDT
 abstime/alpha.*-dec-osf=abstime-solaris-1947
 abstime/i.86-pc-solaris=abstime-solaris-1947
 abstime/sparc-sun-solaris=abstime-solaris-1947
@@ -31,8 +29,8 @@ geometry/sparc-sun-solaris=geometry-solaris-precision
 geometry/sparc.*-linux-gnu=geometry-solaris-precision
 geometry/alpha.*-linux-gnu=geometry-solaris-precision
 geometry/.*-beos=geometry-intel-beos
-horology/.*-aix4=horology-1947-PDT
-horology/.*-irix6=horology-1947-PDT
+horology/.*-aix4=horology-no-DST-before-1970
+horology/.*-irix6=horology-no-DST-before-1970
 horology/alpha.*-dec-osf=horology-solaris-1947
 horology/.*-cygwin=horology-no-DST-before-1970
 horology/hppa=horology-no-DST-before-1970
@@ -74,8 +72,6 @@ int4/sparc-sun-solaris=int4-too-large
 int4/.*-sysv5uw=int4-too-large
 int4/.*-beos=int4-range-error
 int8/.*-qnx=int8-exp-three-digits
-tinterval/.*-aix4=tinterval-1947-PDT
-tinterval/.*-irix6=tinterval-1947-PDT
 tinterval/alpha.*-dec-osf=tinterval-solaris-1947
 tinterval/i.86-pc-solaris=tinterval-solaris-1947
 tinterval/sparc-sun-solaris=tinterval-solaris-1947