Try checking if you're getting some error in the execution of your sql statements.

...
        FETCH returned_cursor INTO returned_row;
        :id := returned_row.id;
        EXCEPTION when others then
        :id := SQLERRM;
        END;
    });
    $func->bind_param(":parameter1", $parameters[1]);
    $func->bind_param_inout(":id", \$return_value, 1000);
    $func->execute;    
    };
...
[download]

Maybe you'll get an hint on what may be happening.

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olus