diff --git a/openerp/addons/base/ir/ir_http.py b/openerp/addons/base/ir/ir_http.py
index 7d0c4be8bc1..a4eaf216381 100644
--- a/openerp/addons/base/ir/ir_http.py
+++ b/openerp/addons/base/ir/ir_http.py
@@ -15,9 +15,7 @@ from openerp.osv import osv, orm
 
 _logger = logging.getLogger(__name__)
 
-
-# FIXME: replace by proxy on request.uid?
-_uid = object()
+UID_PLACEHOLDER = object()
 
 class ModelConverter(werkzeug.routing.BaseConverter):
 
@@ -29,7 +27,7 @@ class ModelConverter(werkzeug.routing.BaseConverter):
     def to_python(self, value):
         m = re.match(self.regex, value)
         return request.registry[self.model].browse(
-            request.cr, _uid, int(m.group(1)), context=request.context)
+            request.cr, UID_PLACEHOLDER, int(m.group(1)), context=request.context)
 
     def to_url(self, value):
         return value.id
@@ -46,7 +44,7 @@ class ModelsConverter(werkzeug.routing.BaseConverter):
         # TODO:
         # - raise routing.ValidationError() if no browse record can be createdm
         # - support slug
-        return request.registry[self.model].browse(request.cr, _uid, [int(i) for i in value.split(',')], context=request.context)
+        return request.registry[self.model].browse(request.cr, UID_PLACEHOLDER, [int(i) for i in value.split(',')], context=request.context)
 
     def to_url(self, value):
         return ",".join(i.id for i in value)
@@ -108,8 +106,12 @@ class ir_http(osv.AbstractModel):
 
         # post process arg to set uid on browse records
         for arg in arguments.itervalues():
-            if isinstance(arg, orm.browse_record) and arg._uid is _uid:
+            if isinstance(arg, orm.browse_record) and arg._uid is UID_PLACEHOLDER:
                 arg._uid = request.uid
+                try:
+                    arg[arg._rec_name]
+                except KeyError:
+                    return self._handle_exception(werkzeug.exceptions.NotFound())
 
         # set and execute handler
         try: