t2flow does not work with T3 server

Sending a t2flow to a tomcat hosted T3 server results in a "failed to build workflow run worker" and a report that the file is using the wrong namespace when it does not appear to be.

eg curl -k -X POST -d @Fetch_today_s_xkcd_comic-v1.t2flow --header "Content-Type:application/vnd.taverna.t2flow+xml" http://taverna:taverna@192.168.0.5:8080/taverna-server/rest/runs
where the workflow file is https://www.myexperiment.org/workflows/824.html
I have also tried with a t1 workflow using content-type "application/xml" which also failed though I'm not sure whether the server is supposed to support that or not.