diff --git a/src/backend/libpq/pqformat.c b/src/backend/libpq/pqformat.c
index 52144eb4c86952a5ff19f5b0a92e186c7c8842fd..efbd0b1e95a39ea55f77310ccf7404aa76304523 100644
--- a/src/backend/libpq/pqformat.c
+++ b/src/backend/libpq/pqformat.c
@@ -24,7 +24,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- *	$PostgreSQL: pgsql/src/backend/libpq/pqformat.c,v 1.37 2004/12/31 21:59:50 pgsql Exp $
+ *	$PostgreSQL: pgsql/src/backend/libpq/pqformat.c,v 1.38 2005/09/24 15:34:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -501,8 +501,12 @@ pq_getmsgint64(StringInfo msg)
 	l32 = ntohl(l32);
 
 #ifdef INT64_IS_BUSTED
-	/* just lose the high half */
+	/* error out if incoming value is wider than 32 bits */
 	result = l32;
+	if ((result < 0) ? (h32 != -1) : (h32 != 0))
+		ereport(ERROR,
+				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+				 errmsg("binary value is out of range for type bigint")));
 #else
 	result = h32;
 	result <<= 32;