XMLDecl => 1  or  XMLDecl => 'string'  *# out - handy*
    If you want the output from "XMLout()" to start with the optional XML
    declaration, simply set the option to '1'. The default XML declaration
    is:

            <?xml version='1.0' standalone='yes'?>

    If you want some other string (for example to declare an encoding
    value), set the value of this option to the complete string you require.