diff --git a/addons/web/common/http.py b/addons/web/common/http.py
index 6e4cbaacaaa..681a38384a2 100644
--- a/addons/web/common/http.py
+++ b/addons/web/common/http.py
@@ -334,7 +334,7 @@ def session_context(request, storage_path, session_cookie='sessionid'):
                 and not value.jsonp_requests
                 and value._creation_time + (60*5) < time.time()  # FIXME do not use a fixed value
             ):
-                _logger.info('remove session %s', key)
+                _logger.debug('remove session %s', key)
                 del request.session[key]
 
         with session_lock:
diff --git a/addons/web/controllers/main.py b/addons/web/controllers/main.py
index 7081ce3ce32..191f184da5b 100644
--- a/addons/web/controllers/main.py
+++ b/addons/web/controllers/main.py
@@ -37,6 +37,9 @@ def concat_xml(file_list):
     concat: concatenation of file content
     timestamp: max(os.path.getmtime of file_list)
     """
+    if not file_list:
+        return '', None
+
     root = None
     files_timestamp = 0
     for fname in file_list:
@@ -56,12 +59,15 @@ def concat_xml(file_list):
     return ElementTree.tostring(root, 'utf-8'), files_timestamp
 
 
-def concat_files(file_list, reader=None):
+def concat_files(file_list, reader=None, intersperse=""):
     """ Concatenate file content
     return (concat,timestamp)
     concat: concatenation of file content, read by `reader`
     timestamp: max(os.path.getmtime of file_list)
     """
+    if not file_list:
+        return '', None
+
     if reader is None:
         def reader(f):
             with open(f) as fp:
@@ -75,7 +81,7 @@ def concat_files(file_list, reader=None):
             files_timestamp = ftime
 
         files_content.append(reader(fname))
-    files_concat = "".join(files_content)
+    files_concat = intersperse.join(files_content)
     return files_concat,files_timestamp
 
 html_template = """<!DOCTYPE html>
@@ -180,7 +186,7 @@ class WebClient(openerpweb.Controller):
     @openerpweb.httprequest
     def js(self, req, mods=None):
         files = [f[0] for f in self.manifest_glob(req, mods, 'js')]
-        content,timestamp = concat_files(files)
+        content, timestamp = concat_files(files, intersperse=';')
         # TODO use timestamp to set Last mofified date and E-tag
         return req.make_response(content, [('Content-Type', 'application/javascript')])
 
@@ -431,7 +437,7 @@ class Session(openerpweb.Controller):
     @openerpweb.jsonrequest
     def modules(self, req):
         # Compute available candidates module
-        loadable = openerpweb.addons_manifest.iterkeys()
+        loadable = openerpweb.addons_manifest
         loaded = req.config.server_wide_modules
         candidates = [mod for mod in loadable if mod not in loaded]
 
diff --git a/addons/web/static/src/js/chrome.js b/addons/web/static/src/js/chrome.js
index 7af729205be..32a70d587a7 100644
--- a/addons/web/static/src/js/chrome.js
+++ b/addons/web/static/src/js/chrome.js
@@ -1124,8 +1124,11 @@ openerp.web.WebClient = openerp.web.Widget.extend(/** @lends openerp.web.WebClie
         this.$element.children().remove();
     },
     do_reload: function() {
-        return this.session.session_reload().pipe(
-            $.proxy(this.menu, 'do_reload'));
+        var self = this;
+        return this.session.session_reload().pipe(function () {
+            openerp.connection.load_modules(true).pipe(
+                self.menu.proxy('do_reload')); });
+
     },
     do_notify: function() {
         var n = this.notification;
diff --git a/addons/web/static/src/js/core.js b/addons/web/static/src/js/core.js
index 0584c49f6b2..b36e576ae47 100644
--- a/addons/web/static/src/js/core.js
+++ b/addons/web/static/src/js/core.js
@@ -676,27 +676,31 @@ openerp.web.Connection = openerp.web.CallbackEnabled.extend( /** @lends openerp.
     },
     /**
      * Load additional web addons of that instance and init them
+     *
+     * @param {Boolean} [no_session_valid_signal=false] prevents load_module from triggering ``on_session_valid``.
      */
-    load_modules: function() {
+    load_modules: function(no_session_valid_signal) {
         var self = this;
         return this.rpc('/web/session/modules', {}).pipe(function(result) {
-            self.module_list = result;
             var lang = self.user_context.lang;
             var params = { mods: ["web"].concat(result), lang: lang};
-            var modules = self.module_list.join(',');
+            var to_load = _.difference(result, self.module_list).join(',');
+            self.module_list = result;
             return $.when(
-                self.rpc('/web/webclient/csslist', {mods: modules}, self.do_load_css),
-                self.rpc('/web/webclient/qweblist', {mods: modules}).pipe(self.do_load_qweb),
+                self.rpc('/web/webclient/csslist', {mods: to_load}, self.do_load_css),
+                self.rpc('/web/webclient/qweblist', {mods: to_load}).pipe(self.do_load_qweb),
                 self.rpc('/web/webclient/translations', params).pipe(function(trans) {
                     openerp.web._t.database.set_bundle(trans);
                     var file_list = ["/web/static/lib/datejs/globalization/" + lang.replace("_", "-") + ".js"];
-                    return self.rpc('/web/webclient/jslist', {mods: modules}).pipe(function(files) {
+                    return self.rpc('/web/webclient/jslist', {mods: to_load}).pipe(function(files) {
                         return self.do_load_js(file_list.concat(files)); 
                     });
                 })
             ).then(function() {
                 self.on_modules_loaded();
-                self.on_session_valid();
+                if (!no_session_valid_signal) {
+                    self.on_session_valid();
+                }
             });
         });
     },
@@ -738,6 +742,7 @@ openerp.web.Connection = openerp.web.CallbackEnabled.extend( /** @lends openerp.
         _.each(files, function(file) {
             self.qweb_mutex.exec(function() {
                 return self.rpc('/web/proxy/load', {path: file}).pipe(function(xml) {
+                    if (!xml) { return; }
                     openerp.web.qweb.add_template(_.str.trim(xml));
                 });
             });