diff --git a/jedi/api/interpreter.py b/jedi/api/interpreter.py
index eaf3a63d..6702cf80 100644
--- a/jedi/api/interpreter.py
+++ b/jedi/api/interpreter.py
@@ -27,11 +27,11 @@ class MixedModuleContext(Context):
         self.evaluator = evaluator
         self._namespaces = namespaces
 
-        raise NotImplementedError("module names")
         self._namespace_objects = [NamespaceObject(n) for n in namespaces]
         self._module_context = ModuleContext(
             evaluator, tree_module,
             path=path,
+            string_names=('__main__',),
             code_lines=code_lines
         )
         self.tree_node = tree_module
diff --git a/jedi/evaluate/compiled/mixed.py b/jedi/evaluate/compiled/mixed.py
index 64f0105f..82e0703c 100644
--- a/jedi/evaluate/compiled/mixed.py
+++ b/jedi/evaluate/compiled/mixed.py
@@ -203,16 +203,17 @@ def _create(evaluator, access_handle, parent_context, *args):
     if parent_context.tree_node.get_root_node() == module_node:
         module_context = parent_context.get_root_context()
     else:
-        raise NotImplementedError('module misses string_names arg')
+        # TODO this __name__ is probably wrong.
+        name = compiled_object.get_root_context().py__name__()
+        string_names = tuple(name.split('.'))
         module_context = ModuleContext(
             evaluator, module_node,
             path=path,
+            string_names=string_names,
             code_lines=code_lines,
         )
-        # TODO this __name__ is probably wrong.
-        name = compiled_object.get_root_context().py__name__()
         if name is not None:
-            imports.add_module_to_cache(evaluator, name, module_context)
+            evaluator.module_cache.add(string_names, ContextSet(module_context))
 
     tree_context = module_context.create_context(
         tree_node,
diff --git a/jedi/evaluate/sys_path.py b/jedi/evaluate/sys_path.py
index 8fb24781..d015d846 100644
--- a/jedi/evaluate/sys_path.py
+++ b/jedi/evaluate/sys_path.py
@@ -151,9 +151,9 @@ def _get_paths_from_buildout_script(evaluator, buildout_script_path):
         return
 
     from jedi.evaluate.context import ModuleContext
-    raise NotImplementedError("No module string_names, yet")
     module = ModuleContext(
         evaluator, module_node, buildout_script_path,
+        string_names=None,
         code_lines=get_cached_code_lines(evaluator.grammar, buildout_script_path),
     )
     for path in check_sys_path_modifications(module):