Invoking stopServers method of the server group requires new parameter in JBoss ON 3.2.x

Issue

• After migration from JBoss ON 3.1.2 to JBoss ON 3.2.2, our script that invokes stopServers() server group's method fails with the exception:

org.mozilla.javascript.EvaluatorException: Can't find method org.rhq.bindings.client.ResourceClientProxy_$$_javassist_0.stopServers(). (<Unknown source>#1) in <Unknown source> at line number 1
gs.stopServers()

• Execution of the script below fails in JBoss ON 3.2.2 while the same worked fine in JBoss ON 3.1.2:

var rscType = ResourceTypeManager.getResourceTypeByNameAndPlugin("ServerGroup", "JBossAS7")
var rc = new ResourceCriteria()
rc.addFilterName(appName)
rc.addFilterParentResourceName("Domain")
rc.addFilterResourceTypeId(rscType.id)
var resources = ResourceManager.findResourcesByCriteria(rc)
var resource = resources.get(0)
gs = ProxyFactory.getResource(resource.id)
gs.stopServers()
....

• What is the new parameter that is needed when executing stopServers server group's method?
• Is there a document that explains the new parameter in stopServers, startServers and restartServers server group's methods?