{HEAD ~ Method} and apparatus for implementing an extensible authentication mechanism in {TAIL ~ a web application server} 
{ HEAD ~ Method } and apparatus for implementing an extensible authentication mechanism in { TAIL ~ a web application server }
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL