Description
bool 
fdf_set_encoding ( resource fdf_document, string encoding)
   fdf_set_encoding() sets the character
   encoding in FDF document fdf_document. 
   encoding should be the valid encoding 
   name. Currently the following values are supported: 
   "Shift-JIS", "UHC",
   "GBK","BigFive".
   An empty string resets the encoding to the default PDFDocEncoding/Unicode
   scheme.