SQL error using sqlanywhere php API sasql_query()

Question

I'm having problem executing a specific query using php API from sqlanywhere 12.

It only happens with SET OPTION query.

<?php
    // setup omitted for clarity here
    $result = sasql_query( $conn, "SET OPTION PUBLIC.AjusteFuso = '0'" );
    // clean up omitted for clarity here
?>

I receive the following exception:

 AjusteFuso' is an unknown option SET OPTION PUBLIC.AjusteFuso = '0'

But this is not true, it is known option in my database!

1 - others select/update/delete/insert works normal as expected.

2 - SET OPTION works ok if i test it using sybase central.

This same query was working normal using sql anywhere 9 with sybase_query() old API.