I'm ready to break something

I cannot for the life of me figure out why this won’t work.

I have a text file source.txt whose sole contents are:

loc=news2.xml

Then this bit of code:


lv = new LoadVars();
lv.onLoad = function() {
    where = this.loc;
}
lv.load("source.txt");
trace(where);

It keeps returning undefined. What’s the problem!? I’ve tried tracing “_root.where” also, but it gives the same result (or lack thereof). I copied this directly from a tutorial on here, just to make sure I didn’t type something wrong. This is making me crazy.