diff --git a/addons/web/common/http.py b/addons/web/common/http.py
index cc76a554693..a1d28536cd4 100644
--- a/addons/web/common/http.py
+++ b/addons/web/common/http.py
@@ -452,7 +452,7 @@ class Root(object):
 
         static_dirs = self._load_addons(openerp_addons_namespace)
         if options.serve_static:
-            self.dispatch = werkzeug.wsgi.SharedDataMiddleware(
+            self.dispatch = SuperSharedDataMiddleware(
                 self.dispatch, static_dirs, cache=False)
 
         if options.session_storage:
@@ -555,6 +555,66 @@ class Root(object):
                         return m
                 ps, _slash, meth = ps.rpartition('/')
         return None
+    
+class SuperSharedDataMiddleware(werkzeug.wsgi.SharedDataMiddleware):
+    def __call__(self, environ, start_response):
+        import os
+        import mimetypes
+        import werkzeug.http
+        # sanitize the path for non unix systems
+        cleaned_path = environ.get('PATH_INFO', '').strip('/')
+        for sep in os.sep, os.altsep:
+            if sep and sep != '/':
+                cleaned_path = cleaned_path.replace(sep, '/')
+        path = '/'.join([''] + [x for x in cleaned_path.split('/')
+                                if x and x != '..'])
+        file_loader = None
+        for search_path, loader in self.exports.iteritems():
+            if search_path == path:
+                real_filename, file_loader = loader(None)
+                if file_loader is not None:
+                    break
+            if not search_path.endswith('/'):
+                search_path += '/'
+            if path.startswith(search_path):
+                real_filename, file_loader = loader(path[len(search_path):])
+                if file_loader is not None:
+                    break
+        if file_loader is None or not self.is_allowed(real_filename):
+            return self.app(environ, start_response)
+
+        guessed_type = mimetypes.guess_type(real_filename)
+        mime_type = guessed_type[0] or self.fallback_mimetype
+        f, mtime, file_size = file_loader()
+        
+        etag = self.generate_etag(mtime, file_size, real_filename)
+        modified = werkzeug.http.is_resource_modified(environ, etag, last_modified=mtime)
+        
+        headers = [('Date', werkzeug.http.http_date())]
+        if self.cache:
+            timeout = self.cache_timeout
+            headers += [
+                ('Etag', '"%s"' % etag),
+                ('Cache-Control', 'max-age=%d, public' % timeout)
+            ]
+            if modified:
+                headers.append(('Expires', werkzeug.http.http_date(time() + timeout)))
+        else:
+            headers.append(('Cache-Control', 'no-cache'))
+            
+        if not modified:
+            f.close()
+            start_response('304 Not Modified', headers)
+            return []
+
+        headers.extend((
+            ('Content-Type', mime_type),
+            ('Content-Length', str(file_size)),
+            ('Last-Modified', werkzeug.http.http_date(mtime))
+        ))
+        start_response('200 OK', headers)
+        return werkzeug.wsgi.wrap_file(environ, f)
+
 
 class LibException(Exception):
     """ Base of all client lib exceptions """