diff --git a/include/ldap_pvt_uc.h b/include/ldap_pvt_uc.h
index 5b4bcc06ed..bfd236ef05 100644
--- a/include/ldap_pvt_uc.h
+++ b/include/ldap_pvt_uc.h
@@ -82,7 +82,7 @@ LDAP_F (char *) ldap_utf8_strpbrk( const char* str, const char *set);
 LDAP_F (char*) ldap_utf8_strtok( char* sp, const char* sep, char **last);
 
 /* Optimizations */
-#define LDAP_UTF8_ISASCII(p) ( * (const unsigned char *) (p) < 0x100 )
+#define LDAP_UTF8_ISASCII(p) ( * (const unsigned char *) (p) < 0x80 )
 #define LDAP_UTF8_CHARLEN(p) ( LDAP_UTF8_ISASCII(p) \
 	? 1 : ldap_utf8_charlen((p)) )
 #define LDAP_UTF8_OFFSET(p) ( LDAP_UTF8_ISASCII(p) \
diff --git a/libraries/libldap/utf-8.c b/libraries/libldap/utf-8.c
index 1523b7b4a4..70734d7504 100644
--- a/libraries/libldap/utf-8.c
+++ b/libraries/libldap/utf-8.c
@@ -29,7 +29,7 @@
 #include "ldap_defaults.h"
 
 #undef ISASCII
-#define ISASCII(uc)	((uc) < 0x100)
+#define ISASCII(uc)	((uc) < 0x80)
 
 /*
  * Basic UTF-8 routines
@@ -264,7 +264,7 @@ int ldap_utf8_copy( char* dst, const char *src )
 
 /*
  * UTF-8 ctype routines
- * Only deals with characters < 0x100 (ie: US-ASCII)
+ * Only deals with characters < 0x80 (ie: US-ASCII)
  */
 
 int ldap_utf8_isascii( const char * p )