Question about EXI Draft - XML declaraion

Dear W3C EXI WG members,

I have a question about this draft specification.

EXI dose not support the XML declaration - character encoding scheme,
standalone, version. (ref. B.1).
But why does not it support the XML declaration?
I think "character encoding scheme" is not necessary, but I cannot
understand why the "standalone", "version" is not suppoerted.

Regards,
Keisuke Tamiya (tamiya.keisuke@canon.co.jp)