Autocast script of peter e in PostgreSQL 8.3

If i use this script
http://people.planetpostgresql.org/peter/index.php?/archives/18-Readding-implicit-casts-in-PostgreSQL-8.3.html
in PostgreSql 8.3 to reactivate autocast i get the following problems:

*without autocast* script (i learned that 8.3 does autocast if one of
the || parameters is Text(or Char/Varchar) :-P ):

demo=# SELECT 1||'~'||1;
?column?
----------
1~1
(1 row)

*with autocast:

*SCDS=# SELECT 1||'~'||1;
ERROR: operator is not unique: integer || unknown at character 9
HINT: Could not choose a best candidate operator. You might need to add
explicit type casts.
LINE 1: SELECT 1||'~'||1;

SCDS=# SELECT 1||'~'::TEXT||1;
ERROR: operator is not unique: integer || text at character 9
HINT: Could not choose a best candidate operator. You might need to add
explicit type casts.
LINE 1: SELECT 1||'~'::TEXT||1;

Any hints?

Daniel.