When I try to shut down the server, I get this error:

       mod = imp.load_module('openerp.addons.' + module_part, f, path, descr)
  File "/Users/imac/Desktop/openerp/openerp/addons/account_test/__init__.py", line 1, in <module>
    import account_test
  File "/Users/imac/Desktop/openerp/openerp/addons/account_test/account_test.py", line 32, in <module>
    import pooler
ImportError: No module named pooler

Any suggetions would be great.