I have Varnish 3.0.2 on Redhat and service varnish start fails after I added vcl_hash section. I did varnishd and then loaded the vcl using vcl.load

vcl.load default default.vcl

Message from VCC-compiler:
Unknown variable 'req.hash'
At: ('input' Line 24 Pos 9)
    set req.hash += req.url;
--------########------------

Running VCC-compiler failed, exit 1

cat default.vcl

backend default {
  .host = "127.0.0.1";
  .port = "8080";
}

sub vcl_recv {
  if( req.url ~ "\.(css|js|jpg|jpeg|png|swf|ico|gif|jsp)$" ) {
    unset req.http.cookie;
  }
}

sub vcl_hash {
  set req.hash += req.url;
  set req.hash += req.http.host;
  if( req.httpCookie == "JSESSIONID" ) {
    set req.http.X-Varnish-Hashed-On = regsub( req.http.Cookie, "^.*?JSESSIONID=([a-zA-z0-9]{32}\.[a-zA-Z0-9]+)([\s$\n])*.*?$", "\1" );
    set req.hash += req.http.X-Varnish-Hashed-On;
  }
  return(hash);
}

What could be wrong?