diff --git a/src/backend/utils/adt/oracle_compat.c b/src/backend/utils/adt/oracle_compat.c
index d0d1fc5fecfeb38a8d6b93961e8dc7494c27944d..5dd9a44ccf8fa2128f54400116e9b619289ac12c 100644
--- a/src/backend/utils/adt/oracle_compat.c
+++ b/src/backend/utils/adt/oracle_compat.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	$PostgreSQL: pgsql/src/backend/utils/adt/oracle_compat.c,v 1.60 2005/05/07 15:18:17 momjian Exp $
+ *	$PostgreSQL: pgsql/src/backend/utils/adt/oracle_compat.c,v 1.61 2005/08/24 17:50:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -149,6 +149,117 @@ wcstotext(const wchar_t *str, int ncodes)
 #endif   /* USE_WIDE_UPPER_LOWER */
 
 
+/*
+ * On Windows, the "Unicode" locales assume UTF16 not UTF8 encoding.
+ * To make use of the upper/lower functionality, we need to map UTF8 to
+ * UTF16, which for some reason mbstowcs and wcstombs won't do for us.
+ * This conversion layer takes care of it.
+ */
+
+#ifdef WIN32
+
+/* texttowcs for the case of UTF8 to UTF16 */
+static wchar_t *
+win32_utf8_texttowcs(const text *txt)
+{
+	int			nbytes = VARSIZE(txt) - VARHDRSZ;
+	wchar_t    *result;
+	int         r;
+
+	/* Overflow paranoia */
+	if (nbytes < 0 ||
+		nbytes > (int) (INT_MAX / sizeof(wchar_t)) -1)
+		ereport(ERROR,
+				(errcode(ERRCODE_OUT_OF_MEMORY),
+				 errmsg("out of memory")));
+
+	/* Output workspace cannot have more codes than input bytes */
+	result = (wchar_t *) palloc((nbytes + 1) * sizeof(wchar_t));
+
+	/* stupid Microsloth API does not work for zero-length input */
+	if (nbytes == 0)
+		r = 0;
+	else
+	{
+		/* Do the conversion */
+		r = MultiByteToWideChar(CP_UTF8, 0, VARDATA(txt), nbytes,
+								result, nbytes);
+
+		if (!r)					/* assume it's NO_UNICODE_TRANSLATION */
+		{
+			/* see notes above about error reporting */
+			pg_verifymbstr(VARDATA(txt), nbytes, false);
+			ereport(ERROR,
+					(errcode(ERRCODE_CHARACTER_NOT_IN_REPERTOIRE),
+					 errmsg("invalid multibyte character for locale"),
+					 errhint("The server's LC_CTYPE locale is probably incompatible with the database encoding.")));
+		}
+	}
+
+	Assert(r <= nbytes);
+	result[r] = 0;
+
+	return result;
+}
+
+/* wcstotext for the case of UTF16 to UTF8 */
+static text *
+win32_utf8_wcstotext(const wchar_t *str)
+{
+	text		*result;
+	int			 nbytes;
+	int			 r;
+
+	nbytes = WideCharToMultiByte(CP_UTF8, 0, str, -1, NULL, 0, NULL, NULL);
+	if (nbytes == 0)			/* shouldn't happen */
+		ereport(ERROR,
+				(errcode(ERRCODE_CHARACTER_NOT_IN_REPERTOIRE),
+				 errmsg("UTF16 to UTF8 translation failed: %lu",
+						GetLastError())));
+
+	result = palloc(nbytes+VARHDRSZ);
+
+	r = WideCharToMultiByte(CP_UTF8, 0, str, -1, VARDATA(result), nbytes,
+							NULL, NULL);
+	if (r == 0)					/* shouldn't happen */
+		ereport(ERROR,
+				(errcode(ERRCODE_CHARACTER_NOT_IN_REPERTOIRE),
+				 errmsg("UTF16 to UTF8 translation failed: %lu",
+						GetLastError())));
+
+	VARATT_SIZEP(result) = nbytes + VARHDRSZ - 1; /* -1 to ignore null */
+
+	return result;
+}
+
+/* interface layer to check which encoding is in use */
+
+static wchar_t *
+win32_texttowcs(const text *txt)
+{
+	if (GetDatabaseEncoding() == PG_UTF8)
+		return win32_utf8_texttowcs(txt);
+	else
+		return texttowcs(txt);
+}
+
+static text *
+win32_wcstotext(const wchar_t *str, int ncodes)
+{
+	if (GetDatabaseEncoding() == PG_UTF8)
+		return win32_utf8_wcstotext(str);
+	else
+		return wcstotext(str, ncodes);
+}
+
+/* use macros to cause routines below to call interface layer */
+
+#define texttowcs	win32_texttowcs
+#define wcstotext	win32_wcstotext
+
+#endif /* WIN32 */
+
+
 /********************************************************************
  *
  * lower
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 399da666130a2f57bbb91c7b98919434256e99f5..3182b4eb80154c8200b30605cf779908dc08bd5e 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.131 2005/08/02 16:11:57 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.132 2005/08/24 17:50:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -849,6 +849,8 @@ varstr_cmp(char *arg1, int len1, char *arg2, int len2)
 		char	   *a1p,
 				   *a2p;
 
+#ifndef WIN32
+
 		if (len1 >= STACKBUFLEN)
 			a1p = (char *) palloc(len1 + 1);
 		else
@@ -865,10 +867,87 @@ varstr_cmp(char *arg1, int len1, char *arg2, int len2)
 
 		result = strcoll(a1p, a2p);
 
-		if (len1 >= STACKBUFLEN)
+		if (a1p != a1buf)
 			pfree(a1p);
-		if (len2 >= STACKBUFLEN)
+		if (a2p != a2buf)
 			pfree(a2p);
+
+#else /* WIN32 */
+
+		/* Win32 does not have UTF-8, so we need to map to UTF-16 */
+		if (GetDatabaseEncoding() == PG_UTF8)
+		{
+			int a1len;
+			int a2len;
+			int r;
+
+			if (len1 >= STACKBUFLEN/2)
+			{
+				a1len = len1 * 2 + 2;
+				a1p = palloc(a1len);
+			}
+			else
+			{
+				a1len = STACKBUFLEN;
+				a1p = a1buf;
+			}
+			if (len2 >= STACKBUFLEN/2)
+			{
+				a2len = len2 * 2 + 2;
+				a2p = palloc(a2len);
+			}
+			else
+			{
+				a2len = STACKBUFLEN;
+				a2p = a2buf;
+			}
+
+			/* stupid Microsloth API does not work for zero-length input */
+			if (len1 == 0)
+				r = 0;
+			else
+			{
+				r = MultiByteToWideChar(CP_UTF8, 0, arg1, len1,
+										(LPWSTR) a1p, a1len/2);
+				if (!r)
+					ereport(ERROR,
+							(errmsg("could not convert string to UTF16: %lu",
+									GetLastError())));
+			}
+			((LPWSTR) a1p)[r] = 0;
+
+			if (len2 == 0)
+				r = 0;
+			else
+			{
+				r = MultiByteToWideChar(CP_UTF8, 0, arg2, len2,
+										(LPWSTR) a2p, a2len/2);
+				if (!r)
+					ereport(ERROR,
+							(errmsg("could not convert string to UTF16: %lu",
+									GetLastError())));
+			}
+			((LPWSTR) a2p)[r] = 0;
+
+			errno = 0;
+			result = wcscoll((LPWSTR) a1p, (LPWSTR) a2p);
+			if (result == 2147483647) /* _NLSCMPERROR; missing from mingw headers */
+				ereport(ERROR,
+						(errmsg("could not compare unicode strings: %d",
+								errno)));
+
+			if (a1p != a1buf)
+				pfree(a1p);
+			if (a2p != a2buf)
+				pfree(a2p);
+
+			return result;
+		}
+
+		/* Win32 has strncoll(), so use it to avoid copying */
+		return _strncoll(arg1, arg2, Min(len1, len2));
+
+#endif /* WIN32 */
 	}
 	else
 	{
@@ -2000,7 +2079,7 @@ replace_text(PG_FUNCTION_ARGS)
 
 /*
  * check_replace_text_has_escape_char
- * check whether replace_text has escape char. 
+ * check whether replace_text has escape char.
  */
 static bool
 check_replace_text_has_escape_char(const text *replace_text)
@@ -2175,7 +2254,7 @@ replace_text_regexp(PG_FUNCTION_ARGS)
 
 		/*
 		 * Copy the replace_text. Process back references when the
-		 * replace_text has escape characters. 
+		 * replace_text has escape characters.
 		 */
 		if (have_escape)
 			appendStringInfoRegexpSubstr(str, replace_text, pmatch, src_text);
@@ -2573,7 +2652,7 @@ md5_bytea(PG_FUNCTION_ARGS)
 	PG_RETURN_TEXT_P(result_text);
 }
 
-/* 
+/*
  * Return the size of a datum, possibly compressed
  *
  * Works on any data type