i added a new service definition, http proxy outgoing, with src port 8080 and dst port 1024:65500. Next i added a traffic selector with source: internal ip, service: http proxy outgoing and dst: internal networks. Finally i added this selector to a bandwithpool with a desired limit.
Yes it worked, but its only a freaky work-around to preserve the system load caused by the 'new' http-proxy (no sarcasm [:P]).
I also succesfully configured a trafficselector for outgoing vpn, but limited qos functionality don't let me fulfill my desire of a perfect shaping.
As I wrote here shaping within ipsec devices would be really nice.
