the http_proxy environmental variable for sending SPA packets through an HTTP proxy. The patch also adds support for specifying an HTTP proxy user and password via the following syntax: 'http://username:password@proxy.com:port' or 'http://username:password@proxy.com' git-svn-id: file:///home/mbr/svn/fwknop/trunk@164 510a4753-2344-4c79-9c09-4d669213fbeb