How I can access to variableScope of Event

Hi,

How I Can access to variableScope of Event?

With activiti-cdi I accessed as follows:

public void onTaskStart(
		@Observes @BusinessProcessDefinition("TASKNAME") @StartActivity("STARTED") BusinessProcessEvent event) {
	String variable = (String) event.getVariableScope()
			.getVariable("VARIABLENAME");
}

But the class BusinessProcessEvent do not have the getVariableScope.

Thank you in advance!