Sqlstatement with !=-1 fails

Hello,

I get the following error

pl=# select * from person where id !=-1;
ERROR:  Unable to identify an operator '!=-' for types 'int8' and 'int4'
        You will have to retype this query using an explicit cast

pl=# select * from person where id =-1;
 id | name | last_update_time
----+------+------------------
(0 rows)

However this works fine

pl=# select * from person where id != -1;

This looks like a parser error, note the space added in the select that
works ??

Dave