Using OWSM and BPEL PM behind a proxy

We use OWSM and BPEL PM to consumme services outside our network.
Nothing to fancy so far, we had to modify the JVM settings and add the following parameter:

Dhttp.proxySet=true
Dhttp.proxyHost = proxy_server
Dhttp.proxyPort = listen_port
Dhttp.nonproxyHost = *localhost|*domain.com

in our case this was:
Dhttp.proxySet=true
Dhttp.proxyHost = www-proxy.outsourcing.com
Dhttp.proxyPort = 80
Dhttp.nonproxyHost = *outsourcing.com

Do not forget to add your localhost as non proxy.
The JVM settings can be accessed through the OC4 console or by editing the file

ORACLE_HOME/opmn/conf/opmn.xml

Then we add to consumme an https service and the add the settings:
Dhttps.proxySet=true
Dhttps.proxyHost = www-proxy.outsourcing.com
Dhttps.proxyPort = 80
Dhttps.nonproxyHost = *outsourcing.com

The case has to be exactly that and only a restart of the OC4J instance is not enough- You have to restart the JVM.
Also note that this cannot be changed without a restart.