diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index bdedd83e6e37948b01d76e39b386655f00094fcf..d56cf04bf368d8c85c97f0065afb02237b8c31c6 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.101 2004/03/15 03:29:22 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.102 2004/04/01 22:51:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -276,7 +276,7 @@ float4in(PG_FUNCTION_ARGS)
 	}
 
 	/* skip leading whitespace */
-	while (*num != '\0' && isspace(*num))
+	while (*num != '\0' && isspace((unsigned char) *num))
 		num++;
 
 	errno = 0;
@@ -319,7 +319,7 @@ float4in(PG_FUNCTION_ARGS)
 	}
 
 	/* skip trailing whitespace */
-	while (*endptr != '\0' && isspace(*endptr))
+	while (*endptr != '\0' && isspace((unsigned char) *endptr))
 		endptr++;
 
 	/* if there is any junk left at the end of the string, bail out */
@@ -441,7 +441,7 @@ float8in(PG_FUNCTION_ARGS)
 	}
 
 	/* skip leading whitespace */
-	while (*num != '\0' && isspace(*num))
+	while (*num != '\0' && isspace((unsigned char) *num))
 		num++;
 
 	errno = 0;
@@ -484,7 +484,7 @@ float8in(PG_FUNCTION_ARGS)
 	}
 
 	/* skip trailing whitespace */
-	while (*endptr != '\0' && isspace(*endptr))
+	while (*endptr != '\0' && isspace((unsigned char) *endptr))
 		endptr++;
 
 	/* if there is any junk left at the end of the string, bail out */
diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c
index 8667e53680a1f03dad387863cc154363e6365ab3..03a5c2a000b4297e81bce249ff53ca025f730493 100644
--- a/src/backend/utils/adt/int8.c
+++ b/src/backend/utils/adt/int8.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/int8.c,v 1.52 2004/03/11 02:11:13 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/int8.c,v 1.53 2004/04/01 22:51:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -114,7 +114,7 @@ scanint8(const char *str, bool errorOK, int64 *result)
 	}
 
 	/* allow trailing whitespace, but not other trailing chars */
-	while (*ptr != '\0' && isspace(*ptr))
+	while (*ptr != '\0' && isspace((unsigned char) *ptr))
 		ptr++;
 
 	if (*ptr != '\0')
diff --git a/src/backend/utils/adt/numutils.c b/src/backend/utils/adt/numutils.c
index 17961017fafef0096c83394f51e8d415acfe5dc8..920eb27a7535dc8d6ddce9e3340eb64288b96fa2 100644
--- a/src/backend/utils/adt/numutils.c
+++ b/src/backend/utils/adt/numutils.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/numutils.c,v 1.62 2004/03/11 02:11:13 neilc Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/numutils.c,v 1.63 2004/04/01 22:51:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -88,7 +88,7 @@ pg_atoi(char *s, int size, int c)
 	 * Skip any trailing whitespace; if anything but whitespace
 	 * remains before the terminating character, bail out
 	 */
-	while (*badp != c && isspace(*badp))
+	while (*badp != c && isspace((unsigned char) *badp))
 		badp++;
 
 	if (*badp != c)