Bootstrap 3 - Multi Select

HTML

<script src="//netdna.bootstrapcdn.com/bootstrap/3.1.1/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.1.1/css/bootstrap.min.css">
<div class="col-sm-12">
    <div id="vm" class="tab-pane fade in  active">
        <div class="panel panel-primary">
            <div class="panel-heading">
                <span class="panel-title"><i class="fa fa-linux"></i> Machines Virtuelles</span>
            </div>
            <div class="panel-body">
                <form action="/Lab/Rtx/etabs/edit/0451483t" id="ServerEditForm" method="post" accept-charset="utf-8">
                <div style="display:none;">
                    <input type="hidden" name="_method" value="POST">
                </div>
                <div class="col-md-8">
                    <div class="form-group">
                        <input type="hidden" name="data[Server][0][id]" class="form-control" value="1" id="Server0Id">
                        <div class="controls">
                            <label for="Server0Vm">hosta0451483t</label>
                            <input type="hidden" name="data[Server][0][Vm]" value="" id="Server0Vm_">
                            <select name="data[Server][0][Vm][]" class="multiselect" multiple="multiple" id="Server0Vm">
                                <optgroup label="Lxc">
                                    <option value="ctrlr0451483t">ctrlr0451483t</option>
                                    <option value="ipr0451483t">ipr0451483t</option>
                                    <option value="ldap0451483t">ldap0451483t</option>
                                    <option value="proxy0451483t">proxy0451483t</option>
                                    <option value="fwpeda0451483t">fwpeda0451483t</option>
                                    <option value="opsi0451483t">opsi0451483t</option>
                                    <option value="commr0451483t">commr0451483t</option>
                                 ...

JavaScript

/**
 * bootstrap-multiselect.js
 * https://github.com/davidstutz/bootstrap-multiselect
 *
 * Copyright 2012 - 2014 David Stutz
 *
 * Dual licensed under the BSD-3-Clause and the Apache License, Version 2.0.
 */
!function($) {

    "use strict";// jshint ;_;
    
    if (Array.prototype.forEach === null || Array.prototype.forEach === undefined) {
        Array.prototype.forEach = function (func) {
            var index;
            for (index = 0; index < this.length; ++index) {
                func(this[index]);
            }
        };
    }

    if (typeof ko !== 'undefined' && ko.bindingHandlers && !ko.bindingHandlers.multiselect) {
        ko.bindingHandlers.multiselect = {

            init: function (element, valueAccessor, allBindingsAccessor, viewModel, bindingContext) {

                var listOfSelectedItems = allBindingsAccessor().selectedOptions,
                    config = ko.utils.unwrapObservable(valueAccessor());

                $(element).multiselect(config);

                if (isObservableArray(listOfSelectedItems)) {
                    // Subscribe to the selectedOptions: ko.observableArray
                    listOfSelectedItems.subscribe(function (changes) {
                        var addedArray = [], deletedArray = [];
                        changes.forEach(function (change) {
                            switch (change.status) {
                                case 'added':
                                    addedArray.push(change.value);
                                    break;
                                case 'deleted':
                                    deletedArray.push(change.value);
                                    break;
                            }
                        });
                        if (addedArray.length > 0) {
                            $(element).multiselect('select', addedArray);
                        };
                        if (deletedArray.length > 0) {
                           ...