save file complains encoding incompatibility

[Xah Lee]

i get the following message in emacs whenever i save some files:

Selected encoding mule-utf-16be-with-signature-unix disagrees with 
 utf-16-unix specified by file contents. Â Really save (else edit coding 
 cookies and try again)? (yes or no) 

For example, this html file:
http://xahlee.org/p/monkey_king/x025.html

This behavior is very annoying. (because every 10 secs i save i have to type 
yes) Then, the 
message is not very helpful. For example, although i'm not a elisp programer 
but i've used 
emacs for 6 years for much of its features beyond text editing. It is not clear 
to me what the 
"cookies" referes to in this message, or how to turn the message off.

Thanks.

 Xah
 address@hidden
∑ http://xahlee.org/




In GNU Emacs 21.3.50.1 (powerpc-apple-darwin7.6.0, X toolkit)
 of 2004-11-15 on t.local
configured using `configure '--prefix=/sw' '--without-carbon' '--with-x' 
'--without-gif' '--
infodir=${prefix}/share/info' '--mandir=${prefix}/share/man' 
'--libexecdir=${prefix}/lib' '--
with-x-toolkit=lucid' '--without-toolkit-scroll-bars' 'CPPFLAGS=-I/sw/include' 
'LDFLAGS=-
L/sw/lib''