Hi, I found an issue in JIRA which was closed (http://jira.codehaus.org/browse/ACT-980), but it's quite old and the documentation states that this is supported:
"activiti:async ca be specified on the following bpmn task types: task, serviceTask, scriptTask, businessRuleTask, sendTask, receiveTask, userTask, subProcess, callActivity"
It doesn't seem to be working but is this something planned? Is there a JIRA I can follow for it?
It would be useful to be able to specify a complete sub-process as being async IMHO, configured in the calling process.