diff --git a/frontends/src/quick_frontend/quick_widgets.py b/frontends/src/quick_frontend/quick_widgets.py
index d9b8f823..36e7a45b 100644
--- a/frontends/src/quick_frontend/quick_widgets.py
+++ b/frontends/src/quick_frontend/quick_widgets.py
@@ -40,7 +40,11 @@ def register(base_cls, child_cls=None):
     @param child_cls: inherited class to use when Quick... class is requested, must inherit from base_cls.
         Can be None if it's the base_cls itself which register
     """
-    classes_map[base_cls] = child_cls
+    # FIXME: we use base_cls.__name__ instead of base_cls directly because pyjamas because
+    #        in the second case
+    classes_map[base_cls.__name__] = child_cls
+
+
 class WidgetAlreadyExistsError(Exception):
     pass
 
@@ -66,7 +70,9 @@ class QuickWidgetsManager(object):
         @return: class actually used to create widget
         """
         try:
-            cls = classes_map[class_]
+            # FIXME: we use base_cls.__name__ instead of base_cls directly because pyjamas bugs
+            #        in the second case
+            cls = classes_map[class_.__name__]
         except KeyError:
             cls = class_
         if cls is None:
@@ -81,7 +87,7 @@ class QuickWidgetsManager(object):
         """
         class_ = self.getRealClass(class_)
         try:
-            widgets_map = self._widgets[class_]
+            widgets_map = self._widgets[class_.__name__]
         except KeyError:
             return iter([])
         else:
@@ -139,8 +145,9 @@ class QuickWidgetsManager(object):
         except KeyError:
             hash_ = cls.getWidgetHash(target, _kwargs['profiles'])
 
-        # widget creation or retrieval
-        widgets_map = self._widgets.setdefault(cls, {}) # we sorts widgets by classes
+        ## widget creation or retrieval ##
+
+        widgets_map = self._widgets.setdefault(cls.__name__, {}) # we sorts widgets by classes
         if not cls.SINGLE:
             widget = None # if the class is not SINGLE, we always create a new widget
         else: