"Edit Review Details" errors with "The server is not responding" but the server is ok

There is an issue with the Edit Review Details button in our crucible instance which is pretty much stopping us dead in our tracks.

I get 2 different errors, and I have attached screenshots of both.

• Upon page refresh click the "Edit Review Details" button. We get the following error:
  
• Instead of Reload, click 'Close', then 'Done' and click the "Edit Review Details" button. Now the error becomes:
  
  There is a Error pane behing the empty Edit Review Pane which contains the following errors:

  Error
  Not Found
  Error 2
  A com.opensymphony.xwork.config.ConfigurationException was encountered
  
  There is no Action mapped for namespace /cru and action name edit-detailsundefined. Check if there is such an action name with such namespace defined in the xwork.xml and also if such an action class exists. Check also the log to see if the action class is successfully loaded.