hash with Accept-Encoding

[Ricardo Newbery]

I came across this line in an example vcl which confused me...

sub vcl_hash {
     set req.hash += req.http.Accept-Encoding;
}


This line seemed superfluous to me since it was my impression that  
varnish already took care of this automatically as long as the Vary  
header was set correctly.  Is this not the case?

Ric