// from http://www.phpied.com/javascript-include/
var included_files = new Array();

function include_once(script_filename) {
    function include_dom(script_filename) {
        var html_doc = document.getElementsByTagName('head').item(0);
        var js = document.createElement('script');
        js.setAttribute('language', 'javascript');
        js.setAttribute('type', 'text/javascript');
        js.setAttribute('src', script_filename);
        html_doc.appendChild(js);
        return false;
    }

    function in_array(needle, haystack) {
        for (var i = 0; i < haystack.length; i++) {
            if (haystack[i] == needle) {
                return true;
            }
        }
        return false;
    }

    if (!in_array(script_filename, included_files)) {
        included_files[included_files.length] = script_filename;
        include_dom(script_filename);
    }
}

String.prototype.trim = function() {
    a = this.replace(/^\s+/, '');
    return a.replace(/\s+$/, '');
};