diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 3783e97..b93fc27 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -9405,7 +9405,7 @@ quote_identifier(const char *ident)
 	 * would like to use <ctype.h> macros here, but they might yield unwanted
 	 * locale-specific results...
 	 */
-	safe = ((ident[0] >= 'a' && ident[0] <= 'z') || ident[0] == '_');
+	safe = ((ident[0] >= 'a' && ident[0] <= 'z') || ident[0] == '_' || IS_HIGHBIT_SET(ident[0]));
 
 	for (ptr = ident; *ptr; ptr++)
 	{
@@ -9413,7 +9413,8 @@ quote_identifier(const char *ident)
 
 		if ((ch >= 'a' && ch <= 'z') ||
 			(ch >= '0' && ch <= '9') ||
-			(ch == '_'))
+			(ch == '_') ||
+			(IS_HIGHBIT_SET(ch)))
 		{
 			/* okay */
 		}