--- a/cubicweb/cwconfig.py	Fri Mar 17 16:29:38 2017 +0100
+++ b/cubicweb/cwconfig.py	Tue Mar 21 14:17:26 2017 +0100
@@ -276,6 +276,15 @@
     return cube
 
 
+def _cube_modname(cube):
+    modname = _cube_pkgname(cube)
+    loader = pkgutil.find_loader(modname)
+    if loader:
+        return modname
+    else:
+        return 'cubes.' + cube
+
+
 def _expand_modname(modname):
     """expand modules names `modname` if exists by walking non package submodules
     and yield (submodname, filepath) including `modname` itself
@@ -817,7 +826,8 @@
         for name in ('bootstrap', 'base', 'workflow', 'Bookmark'):
             modnames.append(('cubicweb', 'cubicweb.schemas.' + name))
         for cube in reversed(self.cubes()):
-            for modname, filepath in _expand_modname('cubes.{0}.schema'.format(cube)):
+            for modname, filepath in _expand_modname(
+                    '{0}.schema'.format(_cube_modname(cube))):
                 modnames.append((cube, modname))
         if self.apphome:
             apphome = realpath(self.apphome)
@@ -1335,9 +1345,10 @@
 
     def appobjects_cube_modnames(self, cube):
         modnames = []
+        cube_modname = _cube_modname(cube)
         cube_submodnames = self._sorted_appobjects(self.cube_appobject_path)
         for name in cube_submodnames:
-            for modname, filepath in _expand_modname('.'.join(['cubes', cube, name])):
+            for modname, filepath in _expand_modname('.'.join([cube_modname, name])):
                 modnames.append(modname)
         return modnames
 

--- a/cubicweb/test/unittest_cwconfig.py	Fri Mar 17 16:29:38 2017 +0100
+++ b/cubicweb/test/unittest_cwconfig.py	Tue Mar 21 14:17:26 2017 +0100
@@ -450,9 +450,9 @@
             ('cubicweb', 'cubicweb.schemas.workflow'),
             ('cubicweb', 'cubicweb.schemas.Bookmark'),
             ('bar', 'cubes.bar.schema'),
-            ('foo', 'cubes.foo.schema'),
-            ('foo', 'cubes.foo.schema.a'),
-            ('foo', 'cubes.foo.schema.b'),
+            ('foo', 'cubicweb_foo.schema'),
+            ('foo', 'cubicweb_foo.schema.a'),
+            ('foo', 'cubicweb_foo.schema.b'),
         ]
         # app has schema file
         instance_dir, cubes_dir = (
@@ -497,9 +497,9 @@
             'cubicweb.entities.sources',
             'cubicweb.entities.wfobjs',
             'cubes.bar.hooks',
-            'cubes.foo.entities',
-            'cubes.foo.entities.a',
-            'cubes.foo.hooks',
+            'cubicweb_foo.entities',
+            'cubicweb_foo.entities.a',
+            'cubicweb_foo.hooks',
         ]
         # data1 has entities
         with temp_config('data1', instance_dir, cubes_dir,