diff --git a/addons/point_of_sale/static/src/js/chrome.js b/addons/point_of_sale/static/src/js/chrome.js
index 2e9d6f17885..69aa3c7f902 100644
--- a/addons/point_of_sale/static/src/js/chrome.js
+++ b/addons/point_of_sale/static/src/js/chrome.js
@@ -481,7 +481,7 @@ openerp.point_of_sale.load_chrome = function load_chrome(instance, module){ //mo
             }
 
             var popup = $(QWeb.render('ErrorTracebackPopupWidget',{
-                widget: { title: title , body: body },
+                widget: { options: {title: title , body: body }},
             }));
 
             popup.find('.button').click(function(){
diff --git a/addons/point_of_sale/static/src/js/gui.js b/addons/point_of_sale/static/src/js/gui.js
index 4627abab60b..20e754b07e5 100644
--- a/addons/point_of_sale/static/src/js/gui.js
+++ b/addons/point_of_sale/static/src/js/gui.js
@@ -169,6 +169,11 @@ openerp.point_of_sale.load_gui = function load_gui(instance, module) {
             }
         },
 
+        // is there an active popup ?
+        has_popup: function() {
+            return !!this.current_popup;
+        },
+
         /* ---- Gui: ACCESS CONTROL ---- */
 
         // A Generic UI that allow to select a user from a list.
@@ -280,6 +285,21 @@ openerp.point_of_sale.load_gui = function load_gui(instance, module) {
             });
         },
 
+        /* ---- Gui: SOUND ---- */
+
+        play_sound: function(sound) {
+            var src = '';
+            if (sound === 'error') {
+                src = "/point_of_sale/static/src/sounds/error.wav";
+            } else if (sound === 'bell') {
+                src = "/point_of_sale/static/src/sounds/bell.wav";
+            } else {
+                console.error('Unknown sound: ',sound);
+                return;
+            }
+            $('body').append('<audio src="'+src+'" autoplay="true"></audio>');
+        },
+
         /* ---- Gui: KEYBOARD INPUT ---- */
 
         // This is a helper to handle numpad keyboard input. 
@@ -325,6 +345,12 @@ openerp.point_of_sale.load_gui = function load_gui(instance, module) {
                 }
             }
 
+            // End of input buffer at 12 characters.
+            if (newbuf.length > buffer.length && newbuf.length > 12) {
+                this.play_sound('bell');
+                return buffer.slice(0);
+            }
+
             return newbuf;
         },
     });
diff --git a/addons/point_of_sale/static/src/js/models.js b/addons/point_of_sale/static/src/js/models.js
index 7441e25682b..71d593961de 100644
--- a/addons/point_of_sale/static/src/js/models.js
+++ b/addons/point_of_sale/static/src/js/models.js
@@ -284,7 +284,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             },
         },{
             model:  'pos.category',
-            fields: ['id','name','parent_id','child_id','image'],
+            fields: ['id','name','parent_id','child_id'],
             domain: null,
             loaded: function(self, categories){
                 self.db.add_categories(categories);
@@ -874,6 +874,8 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             this.price = json.price_unit;
             this.set_discount(json.discount);
             this.set_quantity(json.qty);
+            this.id    = json.id;
+            orderline_id = Math.max(this.id+1,orderline_id)
         },
         clone: function(){
             var orderline = new module.Orderline({},{
@@ -910,6 +912,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         // product's unity of measure properties. Quantities greater than zero will not get 
         // rounded to zero
         set_quantity: function(quantity){
+            this.order.assert_editable();
             if(quantity === 'remove'){
                 this.order.remove_orderline(this);
                 return;
@@ -989,6 +992,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             }
         },
         merge: function(orderline){
+            this.order.assert_editable();
             this.set_quantity(this.get_quantity() + orderline.get_quantity());
         },
         export_as_JSON: function() {
@@ -997,6 +1001,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
                 price_unit: this.get_unit_price(),
                 discount: this.get_discount(),
                 product_id: this.get_product().id,
+                id: this.id,
             };
         },
         //used to create a json of the ticket, to be sent to the printer
@@ -1017,6 +1022,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         },
         // changes the base price of the product for this orderline
         set_unit_price: function(price){
+            this.order.assert_editable();
             this.price = round_di(parseFloat(price) || 0, this.pos.dp['Product Price']);
             this.trigger('change',this);
         },
@@ -1145,6 +1151,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
     module.Paymentline = Backbone.Model.extend({
         initialize: function(attributes, options) {
             this.pos = options.pos;
+            this.order = options.order;
             this.amount = 0;
             this.selected = false;
             if (options.json) {
@@ -1161,6 +1168,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         },
         //sets the amount of money on this payment line
         set_amount: function(value){
+            this.order.assert_editable();
             this.amount = round_di(parseFloat(value) || 0, this.pos.currency.decimals);
             this.trigger('change',this);
         },
@@ -1225,6 +1233,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             this.orderlines     = new module.OrderlineCollection();
             this.paymentlines   = new module.PaymentlineCollection(); 
             this.pos_session_id = this.pos.pos_session.id;
+            this.finalized      = false; // if true, cannot be modified.
 
             this.set({ client: null });
 
@@ -1282,7 +1291,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             var paymentlines = json.statement_ids;
             for (var i = 0; i < paymentlines.length; i++) {
                 var paymentline = paymentlines[i][2];
-                var newpaymentline = new module.Paymentline({},{pos: this.pos, json: paymentline});
+                var newpaymentline = new module.Paymentline({},{pos: this.pos, order: this, json: paymentline});
                 this.paymentlines.add(newpaymentline);
 
                 if (i === paymentlines.length - 1) {
@@ -1431,8 +1440,14 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         get_name: function() {
             return this.name;
         },
+        assert_editable: function() {
+            if (this.finalized) {
+                throw new Error('Finalized Order cannot be modified');
+            }
+        },
         /* ---- Order Lines --- */
         add_orderline: function(line){
+            this.assert_editable();
             if(line.order){
                 line.order.remove_orderline(line);
             }
@@ -1456,10 +1471,12 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             return this.orderlines.at(this.orderlines.length -1);
         },
         remove_orderline: function( line ){
+            this.assert_editable();
             this.orderlines.remove(line);
             this.select_orderline(this.get_last_orderline());
         },
         add_product: function(product, options){
+            this.assert_editable();
             options = options || {};
             var attr = JSON.parse(JSON.stringify(product));
             attr.pos = this.pos;
@@ -1514,7 +1531,8 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         },
         /* ---- Payment Lines --- */
         add_paymentline: function(cashregister) {
-            var newPaymentline = new module.Paymentline({},{cashregister:cashregister, pos: this.pos});
+            this.assert_editable();
+            var newPaymentline = new module.Paymentline({},{order: this, cashregister:cashregister, pos: this.pos});
             if(cashregister.journal.type !== 'cash' || this.pos.config.iface_precompute_cash){
                 newPaymentline.set_amount( Math.max(this.get_due(),0) );
             }
@@ -1526,6 +1544,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
             return this.paymentlines.models;
         },
         remove_paymentline: function(line){
+            this.assert_editable();
             if(this.selected_paymentline === line){
                 this.select_paymentline(undefined);
             }
@@ -1701,6 +1720,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         },
         /* ---- Invoice --- */
         set_to_invoice: function(to_invoice) {
+            this.assert_editable();
             this.to_invoice = to_invoice;
         },
         is_to_invoice: function(){
@@ -1709,6 +1729,7 @@ openerp.point_of_sale.load_models = function load_models(instance, module){ //mo
         /* ---- Client / Customer --- */
         // the client related to the current order.
         set_client: function(client){
+            this.assert_editable();
             this.set('client',client);
         },
         get_client: function(){
diff --git a/addons/point_of_sale/static/src/js/popups.js b/addons/point_of_sale/static/src/js/popups.js
index e52d9be9669..e0db66f5392 100644
--- a/addons/point_of_sale/static/src/js/popups.js
+++ b/addons/point_of_sale/static/src/js/popups.js
@@ -87,9 +87,7 @@ openerp.point_of_sale.load_popups = function load_popups(instance, module) {
         template:'ErrorPopupWidget',
         show: function(options){
             this._super(options);
-
-            $('body').append('<audio src="/point_of_sale/static/src/sounds/error.wav" autoplay="true"></audio>');
-
+            this.gui.play_sound('error');
         },
     });
     module.Gui.define_popup({name:'error', widget:module.ErrorPopupWidget});
@@ -138,7 +136,7 @@ openerp.point_of_sale.load_popups = function load_popups(instance, module) {
         show: function(options){
             options = options || {};
             var self = this;
-            this._super();
+            this._super(options);
 
             this.list    = options.list    || [];
             this.renderElement();
@@ -167,19 +165,16 @@ openerp.point_of_sale.load_popups = function load_popups(instance, module) {
         show: function(options){
             options = options || {};
             var self = this;
-            this._super();
+            this._super(options);
 
             this.renderElement();
             this.$('input,textarea').focus();
-            
-            this.$('.button.confirm').click(function(){
-            });
         },
         click_confirm: function(){
-            var value = self.$('input,textarea').val();
-            self.gui.close_popup();
+            var value = this.$('input,textarea').val();
+            this.gui.close_popup();
             if( this.options.confirm ){
-                this.options.confirm.call(self,value);
+                this.options.confirm.call(this,value);
             }
         },
     });
@@ -197,7 +192,7 @@ openerp.point_of_sale.load_popups = function load_popups(instance, module) {
         show: function(options){
             options = options || {};
             var self = this;
-            this._super();
+            this._super(options);
 
             this.inputbuffer = options.value   || '';
             this.renderElement();
diff --git a/addons/point_of_sale/static/src/js/screens.js b/addons/point_of_sale/static/src/js/screens.js
index 9c9149b4fe3..0232fb6aebe 100644
--- a/addons/point_of_sale/static/src/js/screens.js
+++ b/addons/point_of_sale/static/src/js/screens.js
@@ -833,6 +833,9 @@ openerp.point_of_sale.load_screens = function load_screens(instance, module){ //
             });
         },
         button_click: function(){},
+        highlight: function(highlight){
+            this.$el.toggleClass('highlight',!!highlight);
+        },
     });
 
     /* -------- The Product Screen -------- */
@@ -1439,6 +1442,11 @@ openerp.point_of_sale.load_screens = function load_screens(instance, module){ //
             var newbuf = this.gui.numpad_input(this.inputbuffer, input, {'firstinput': this.firstinput});
 
             this.firstinput = (newbuf.length === 0);
+
+            // popup block inputs to prevent sneak editing. 
+            if (this.gui.has_popup()) {
+                return;
+            }
             
             if (newbuf !== this.inputbuffer) {
                 this.inputbuffer = newbuf;
@@ -1572,6 +1580,10 @@ openerp.point_of_sale.load_screens = function load_screens(instance, module){ //
                 self.click_invoice();
             });
 
+            this.$('.js_cashdrawer').click(function(){
+                self.pos.proxy.open_cashbox();
+            });
+
         },
         show: function(){
             this.pos.get_order().clean_empty_paymentlines();
@@ -1626,7 +1638,7 @@ openerp.point_of_sale.load_screens = function load_screens(instance, module){ //
 
         // Check if the order is paid, then sends it to the backend,
         // and complete the sale process
-        validate_order: function() {
+        validate_order: function(force_validation) {
             var self = this;
 
             var order = this.pos.get_order();
@@ -1671,6 +1683,26 @@ openerp.point_of_sale.load_screens = function load_screens(instance, module){ //
                 }
             }
 
+            // if the change is too large, it's probably an input error, make the user confirm.
+            if (!force_validation && (order.get_total_with_tax() * 1000 < order.get_total_paid())) {
+                this.gui.show_popup('confirm',{
+                    title: _t('Please Confirm Large Amount'),
+                    body:  _t('Are you sure that the customer wants to  pay') + 
+                           ' ' + 
+                           this.format_currency(order.get_total_paid()) +
+                           ' ' +
+                           _t('for an order of') +
+                           ' ' +
+                           this.format_currency(order.get_total_with_tax()) +
+                           ' ' +
+                           _t('? Clicking "Confirm" will validate the payment.'),
+                    confirm: function() {
+                        self.validate_order('confirm');
+                    },
+                });
+                return;
+            }
+
             if (order.is_paid_with_cash() && this.pos.config.iface_cashdrawer) { 
 
                     this.pos.proxy.open_cashbox();
diff --git a/addons/point_of_sale/static/src/sounds/bell.wav b/addons/point_of_sale/static/src/sounds/bell.wav
new file mode 100644
index 00000000000..660779c51f2
Binary files /dev/null and b/addons/point_of_sale/static/src/sounds/bell.wav differ
diff --git a/addons/point_of_sale/static/src/xml/pos.xml b/addons/point_of_sale/static/src/xml/pos.xml
index 5547a4c70f7..955cde86837 100644
--- a/addons/point_of_sale/static/src/xml/pos.xml
+++ b/addons/point_of_sale/static/src/xml/pos.xml
@@ -596,7 +596,7 @@
                             </t>
                         </t>
                         <t t-if='widget.pos.config.iface_cashdrawer'>
-                            <div class='button js_invoice'>
+                            <div class='button js_cashdrawer'>
                                 <i class='fa fa-archive' /> Open Cashbox
                             </div>
                         </t>
diff --git a/addons/pos_restaurant/static/src/js/notes.js b/addons/pos_restaurant/static/src/js/notes.js
index 2d60b66d62b..116f9c3709a 100644
--- a/addons/pos_restaurant/static/src/js/notes.js
+++ b/addons/pos_restaurant/static/src/js/notes.js
@@ -47,7 +47,7 @@ openerp.pos_restaurant.load_notes = function(instance,module){
             var line = this.pos.get_order().get_selected_orderline();
             if (line) {
                 this.gui.show_popup('textarea',{
-                    message: _t('Orderline Note'),
+                    title: _t('Add Note'),
                     value:   line.get_note(),
                     confirm: function(note) {
                         line.set_note(note);
diff --git a/addons/pos_restaurant/static/src/js/splitbill.js b/addons/pos_restaurant/static/src/js/splitbill.js
index 70714418430..cc640599512 100644
--- a/addons/pos_restaurant/static/src/js/splitbill.js
+++ b/addons/pos_restaurant/static/src/js/splitbill.js
@@ -167,7 +167,7 @@ openerp.pos_restaurant.load_splitbill = function(instance, module){
         template: 'SplitbillButton',
         button_click: function(){
             if(this.pos.get_order().get_orderlines().length > 0){
-                self.gui.show_screen('splitbill');
+                this.gui.show_screen('splitbill');
             }
         },
     });