function strip_tags (str, allowed_tags)
                {
                    var key = '', allowed = false;
                    var matches = [];    var allowed_array = [];
                    var allowed_tag = '';
                    var i = 0;
                    var k = '';
                    var html = ''; 
                    var replacer = function (search, replace, str) {
                        return str.split(search).join(replace);
                    };
                    // Build allowes tags associative array
                    if (allowed_tags) {
                        allowed_array = allowed_tags.match(/([a-zA-Z0-9]+)/gi);
                    }
                    str += '';

                    // Match tags
                    matches = str.match(/(<\/?[\S][^>]*>)/gi);
                    // Go through all HTML tags
                    for (key in matches) {
                        if (isNaN(key)) {
                                // IE7 Hack
                            continue;
                        }

                        // Save HTML tag
                        html = matches[key].toString();
                        // Is tag not in allowed list? Remove from str!
                        allowed = false;

                        // Go through all allowed tags
                        for (k in allowed_array) {            // Init
                            allowed_tag = allowed_array[k];
                            i = -1;

                            if (i != 0) { i = html.toLowerCase().indexOf('<'+allowed_tag+'>');}
                            if (i != 0) { i = html.toLowerCase().indexOf('<'+allowed_tag+' ');}
                            if (i != 0) { i = html.toLowerCase().indexOf('</'+allowed_tag)   ;}

                            // Determine
                            if (i == 0) {                allowed = true;
                                break;
                            }
                        }
                        if (!allowed) {
                            str = replacer(html, "", str); // Custom replace. No regexing
                        }
                    }
                    return str;
                }