diff --git a/addons/web/controllers/main.py b/addons/web/controllers/main.py
index 9819e5b895b..695b3f4034a 100644
--- a/addons/web/controllers/main.py
+++ b/addons/web/controllers/main.py
@@ -534,14 +534,15 @@ class Home(http.Controller):
     @http.route([
         '/web/css/<xmlid>',
         '/web/css/<xmlid>/<version>',
+        '/web/css.<int:page>/<xmlid>/<version>',
     ], type='http', auth='public')
-    def css_bundle(self, xmlid, version=None, **kw):
+    def css_bundle(self, xmlid, version=None, page=None, **kw):
         try:
             bundle = AssetsBundle(xmlid)
         except QWebTemplateNotFound:
             return request.not_found()
 
-        response = request.make_response(bundle.css(), [('Content-Type', 'text/css')])
+        response = request.make_response(bundle.css(page), [('Content-Type', 'text/css')])
         return make_conditional(response, bundle.last_modified, max_age=BUNDLE_MAXAGE)
 
 class WebClient(http.Controller):
diff --git a/openerp/addons/base/ir/ir_qweb.py b/openerp/addons/base/ir/ir_qweb.py
index 3c3fc70ab67..21b2b2dd476 100644
--- a/openerp/addons/base/ir/ir_qweb.py
+++ b/openerp/addons/base/ir/ir_qweb.py
@@ -33,6 +33,8 @@ from openerp.tools.translate import _
 
 _logger = logging.getLogger(__name__)
 
+MAX_CSS_RULES = 4095
+
 #--------------------------------------------------------------------
 # QWeb template engine
 #--------------------------------------------------------------------
@@ -1142,7 +1144,12 @@ class AssetsBundle(object):
         else:
             url_for = self.context.get('url_for', lambda url: url)
             if css and self.stylesheets:
-                href = '/web/css/%s/%s' % (self.xmlid, self.version)
+                suffix = ''
+                if request:
+                    ua = request.httprequest.user_agent
+                    if ua.browser == "msie" and int((ua.version or '0').split('.')[0]) < 10:
+                        suffix = '.0'
+                href = '/web/css%s/%s/%s' % (suffix, self.xmlid, self.version)
                 response.append('<link href="%s" rel="stylesheet"/>' % url_for(href))
             if js:
                 src = '/web/js/%s/%s' % (self.xmlid, self.version)
@@ -1178,7 +1185,10 @@ class AssetsBundle(object):
             self.set_cache('js', content)
         return content
 
-    def css(self):
+    def css(self, page_number=None):
+        if page_number is not None:
+            return self.css_page(page_number)
+
         content = self.get_cache('css')
         if content is None:
             self.compile_sass()
@@ -1198,12 +1208,43 @@ class AssetsBundle(object):
 
             matches.append(content)
             content = u'\n'.join(matches)
-            if self.css_errors:
-                return content
-            self.set_cache('css', content)
+            if not self.css_errors:
+                self.set_cache('css', content)
+            content = content.encode('utf-8')
 
         return content
 
+    def css_page(self, page_number):
+        content = self.get_cache('css.%d' % (page_number,))
+        if page_number:
+            return content
+        if content is None:
+            css = self.css()
+            re_rules = '([^{]+\{(?:[^{}]|\{[^{}]*\})*\})'
+            re_selectors = '()(?:\s*@media\s*[^{]*\{)?(?:\s*(?:[^,{]*(?:,|\{(?:[^}]*\}))))'
+            css_url = '@import url(\'/web/css.%%d/%s/%s\');' % (self.xmlid, self.version)
+            pages = [[]]
+            page = pages[0]
+            page_selectors = 0
+            for rule in re.findall(re_rules, css):
+                selectors = len(re.findall(re_selectors, rule))
+                if page_selectors + selectors < MAX_CSS_RULES:
+                    page_selectors += selectors
+                    page.append(rule)
+                else:
+                    pages.append([rule])
+                    page = pages[-1]
+                    page_selectors = selectors
+            if len(pages) == 1:
+                pages = []
+            for idx, page in enumerate(pages):
+                self.set_cache("css.%d" % (idx+1), ''.join(page))
+            content = '\n'.join(css_url % i for i in range(1,len(pages)+1))
+            self.set_cache("css.0", content)
+        if not content:
+            return self.css()
+        return content
+
     def get_cache(self, type):
         content = None
         domain = [('url', '=', '/web/%s/%s/%s' % (type, self.xmlid, self.version))]