ImportError: no module named mx

When importing then last oemedical full branch (lp:oemedical) and refreshing the local module list i get the next error:

OpenERP Server Error

Client Traceback (most recent call last):
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\http.py", line 204, in dispatch
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\controllers\main.py", line 1132, in call_button
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\controllers\main.py", line 1120, in _call_kw
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\session.py", line 42, in proxy
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\session.py", line 30, in proxy_method
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\session.py", line 103, in send

Server Traceback (most recent call last):
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\session.py", line 89, in send
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\netsvc.py", line 292, in dispatch_rpc
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\service\web_services.py", line 626, in dispatch
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\osv\osv.py", line 188, in execute_kw
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\osv\osv.py", line 131, in wrapper
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\osv\osv.py", line 197, in execute
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\osv\osv.py", line 185, in execute_cr
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\base\module\wizard\base_module_update.py", line 42, in update_module
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\base\module\module.py", line 617, in update_list
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\web\http.py", line 580, in load_addons
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\.\openerp\modules\module.py", line 133, in load_module
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\oemedical_invoice\__init__.py", line 23, in <module>
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\oemedical_invoice\models\__init__.py", line 23, in <module>
  File "C:\Programs (x86)\OpenERP 7.0-20131113-002526\Server\server\openerp\addons\oemedical_invoice\models\medical_invoice.py", line 26, in <module>
ImportError: No module named mx

-------------------------------------------------------

Obviously is something about lines similar to the "from mx import DateTime" (held in medical_invoice for example)

(im using OpenERP's last version on windows 7)