Sorting special characters in XML file

Hi, hoping someone has and idea of how I can solve the problem of sorting special characters such as à, è, ì etc in an actionscript array. I am working on a dictionary which has been created in XML and loads into Flash. The characters all work in textfields etc but when it comes to sorting the array alphabetically I’m hitting problems with them.

Here’s some of my code:
glossary_xml = new XML();
glossary_xml.onLoad = function(success) {
if (success) {
dictionary(glossary_xml);
}
};
glossary_xml.load(‘glossary.xml’);
var allWords:Array = new Array();

in the dictionary function I basically push the words, their translations, gender etc into the array creating a mulitdimensional array. I’m using the following to sort the array which is sorting numerically first then alphabetically and is case insensitve.

allWords.sortOn(“engWord”, Array.CASEINSENSITIVE);
displayArray(allWords);

My problem is that all words beginning with à, È etc appear at the end of the array. How can I get “à” to have the same weight as “a” and “ì” to have the same weight as “i” etc.

Much thanks to anyone with ideas! Mogs =)