[SR-Users] Websocket transport and forward()

Hi guys, Maybe I'm missing something, but when I have a stateless lb with websockets enabled, and I don't have mhomed set (meaning that I need to set $fs manually), how would I set $du and $fs correctly, if $ru is for example this: sip:bo87fffs@h7h3rerhg50k.invalid;transport=ws I tried all kinds of variants and now starting with the simplest approach possible, doing this for sending out the request to the websocket client: $du = $null; $fs = $null; forward(); What I get is this error message: Jun 27 12:30:53 spce lb[12104]: ERROR: <core> [action.c:437]: do_action(): ERROR: do action: forward: bad uri transport 5 Is there anything special I need to do? Does forward() maybe just not understand WS transport? I'm using kamailio 4.0.2. Any help is greatly appreciated! Andreas