I am using jQuery's ajax method to acquire a static JSON file. The data is loaded from the local file system, hence there is no server, so I can't change the mime type.

This works fin in Safari, but Firefox (3.6.3) reports the file to be "not well-formed". I am aware of, and have reviewed, a similar post here on Stack Overflow:

http://stackoverflow.com/questions/677902/not-well-formed-error-in-firefox-when-loading-json-file-with-xmlhttprequest

I believe my JSON is well-formed:

{
    "_": ["appl", "goog", "yhoo", "vz", "t"]
}

My ajax call is straightforward:

$.ajax({
    url: 'data/tickers.json', 
    dataType: 'json',
    async: true,
    data: null,
    success: function(data, textStatus, request) {
        callback(data);
    }
});

If I wrap the JSON with a document tag:

<document>JSON data</document>

as was mentioned in the above referenced posted question, the ajax call fails with a parserror.

So: is there a way to avoid the Firefox warning when reading in client-side JSON files?