--- src/backend/commands/copy.c.orig	2005-09-01 15:07:01.000000000 +0200
+++ src/backend/commands/copy.c	2005-09-01 15:08:45.000000000 +0200
@@ -2657,7 +2657,7 @@
 static int
 GetDecimalFromHex(char hex)
 {
-	if (isdigit(hex))
+	if (isdigit((unsigned char)hex))
 		return hex - '0';
 	else
 		return tolower(hex) - 'a' + 10;
@@ -2802,7 +2802,7 @@
 						{
 							char hexchar = *cur_ptr;
 
-							if (isxdigit(hexchar))
+							if (isxdigit((unsigned char)hexchar))
 							{
 								int val = GetDecimalFromHex(hexchar);
 
@@ -2810,7 +2810,7 @@
 								if (cur_ptr < line_end_ptr)
 								{
 									hexchar = *cur_ptr;
-									if (isxdigit(hexchar))
+									if (isxdigit((unsigned char)hexchar))
 									{
 										cur_ptr++;
 										val = (val << 4) + GetDecimalFromHex(hexchar);