Description:
------------
PHP Code:
<?php 
session_start(); 
$_SESSION['test']='this is a test'; 
echo $_SESSION['test']; 
?> 
If the code above is encoded in ANSI, it works fine.
But if the code is encoded in Unicode or UTF8, it just says "Cannot send session cache limiter - headers already sent ".

Note that when encoded in different formats, the size of the .php file is different. For example, the code above, when encoded in ANSI, is just 90 bytes. but in Utf8, it is 93 bytes and in Unicode, it's 182 bytes.
PHP Code:
session_start(); 
requires to be put before any output, but in UTF8, the 3 extra bytes compared from in ANSI may cause some output.(I think so)

Because I have to echo some non-english characters (such as Chinese), I have to use Unicode or UTF8 encoding, but it doesn't work as mentioned before. I wonder if there's any way to solve this. 


Expected result:
----------------
no matter how .php files are encoded, they just work fine.