In Flash the TEXT that you include or load as an external file using the #include command, the  loadVariables or getURL actions, or the  LoadVars or  XML objects encoding is Unicode, so we don’t get the correct encoding for the files when we are using German characters, Chinese characters etc.  To display other  characters we need to enable the flash property system.useCodepage. It is a Boolean value, by default it is false.

When the command is set to  false , the Flash Player 6 interprets external text files as Unicode. (These files must be encoded as Unicode when you save them.)
When the command is set to true , the Flash Player 6 interprets external text files using the traditional code page of the operating system running the player.

Flash Script 2.0

// Use this any where in your flash script
system.useCodepage  =  true;