[go-nuts] Decoding xml in utf-16 fails

I am using "encoding/xml" to decode xml. Like this:

     import (
         "github.com/paulrosania/go-charset/charset"
         _ "github.com/paulrosania/go-charset/data"
         "encoding/xml"
         "os"
     )

...

     d := xml.NewDecoder(os.Stdin)
     d.CharsetReader = charset.NewReader
     var s myType
     err = d.Decode(&s)

This works for utf-8, iso-8859-1, others... but when I try to decode xml
that is in utf-16 (including a byte order mark) I get:

     XML syntax error on line 1: invalid UTF-8

Using xml.Unmarshal gives the same error.

I know, utf16 is weird, but Windows programs seem to produce it. And
at http://www.opentag.com/xfaq_enc.htm it reads:

     All XML processors must support at least UTF-8 and UTF-16.

So why isn't utf-16 (and utf-32) supported?