Background: Currently we can only set a "process definition key" in a CallActivity (as String or via Expression). This is too limited as it means that always the latest version of the process definition is used.

AT:

• You can specify the "process definition version" additionally in the CallActivity to "early bind" the process definition (as we had it in jBPM 3 and jBPM 4)
• Specify this in the XML like this:

<callActivity id="callSubProcess"
calledElement="checkCreditProcess"
activiti:calledElementBinding="latest|deployment|version"
activiti:calledElementVersion="17">

<extensionElements>
<activiti:in source="someVariableInMainProcess" target="nameOfVariableInSubProcess" />
<activiti:out source="someVariableInSubProcss" target="nameOfVariableInMainProcess" />
</extensionElements>
</callActivity>

Binding Options:
1) LATEST; always call latest version (current semantics)
2) SAME DEPLOYMENT: if called process definition is part of the same deployment as the calling process definition use version from deployment
3) FIXED: fixed version (in this case a processDefinitionId or a version can be provided)