tomcat does not respect keep alive from apache bench and returns Connection: close

tomcat does not respect keep alive from apache bench and returns
Connection: close

I use -k with apache bench (ab) and although I do see my apache bench sends
ab -k -n 10 -c 1 -p postdata -T 'application/json' http://myurl
POST /myurl HTTP/1.0
User-Agent: ApacheBench/2.0.40-dev
Connection: Keep-Alive
Host: myhost:8080
Accept: */*
Content-length: 5667
Content-type: application/json
the response comes back with Connection: close
HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Pragma: no-cache
Cache-Control: no-cache, no-store, max-age=0
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Content-Type: application/json;charset=UTF-8
Content-Language: en-US
Date: Tue, 20 Aug 2013 16:24:34 GMT
Connection: close
note the Connection: close in response..
anyone knows why is doesn't my tomcat respects the keep alive?