operator is not unique: integer || integer

yeah, its clear that an upgrade from 8.1 to 8.3 is impossible for us 
without a major relase.
there are to many changes so the whole project has to be rechecked.

another example:

in 83:

postgres=# SELECT 1::INTEGER||1::INTEGER;
ERROR:  operator does not exist: integer || integer at character 18
HINT:  No operator matches the given name and argument type(s). You 
might need to add explicit type casts.


83 with autocast from peter e:

 ERROR:  operator is not unique: integer || integer


in 81:

postgres=# SELECT 1::INTEGER||1::INTEGER;
 ?column?
----------
 11
(1 row)