import dataObject problem

I try to import dataObject like this.

var myDoc = event.target;
myDoc.importDataObject("myData", "person.xml");

But I get the following warning.

Exception in line 2 of function top_level, script XFA:person[0]:initialize

NotAllowedError: Security settings prevent access to this property or method.
Global.importDataObject:2:initialize undefined:Exec

From where I can configure my security settings ?