ActionScript 3.0 :: Size Limit On String Passed To New XML(str)?

Is there a size limit on strings passed to a new XML variable during construction?I have noticed what I think is a hard limit on the size of strings passed as an argument to the constructor of a new XML variable in actionScript3. I noticed it while trying to pass a large string from javascript to a method in AS3.

Everything works fine as long as the string is less than about 330,000 characters, but as soon as the string I pass gets a little bigger than that (say 360,0000 or more) I always get a js error somewhere in the ExternalInterface and a ActionScript error when the data is recieved. I am running on IE.Here is what I am doing:In javascript I have:

flashPlayer.generateFromXml(text);

Where text is some large string of serialized valid xml.Then in AS3, I have

ExternalInterface.addCallback("generateFromXml", generateFromXml); (called in initialize handler)

then

public function generateFromXml(serializedXml:String):void
{
var x:XML = new XML(serializedXml);
}

Everything works fine until the string exceeds about 340,000 characters, then I get this js error at this line in adobe code:

function __flash__addCallback(instance, name) {
instance[name] = function () {
return eval(instance.CallFunction("<invoke name=""+name+"" returntype="javascript">" + __flash__argumentsToXML(arguments,0) + "</invoke>")); //<<<<<--- line with breakpoint in js debugger

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