XML and text fields

Hey,
Is it possible to place XML-loaded text into a text field that is nested in a movieclip that is not on the stage but being exported from the library? Below is the function that I am using to call it. Everything works fine if the movieclip is placed on the stage, just not if the movieclip is left in the library.

[COLOR=“Blue”]my_xml.onLoad = function(success){
if (success){
_root.mission = this.firstChild.childNodes[0].childNodes[0].firstChild.nodeValue;
trace(_root.mission);[/COLOR]
[COLOR=“Red”]mission_mc.mission_txt.text = _root.mission;[/COLOR]<text field
[COLOR=“blue”]}
}[/COLOR]

much appreciated.

[Flash 8]