I have updated my Galaxy distribution today to the latest version 15.03 and the history panel is not being shown. The history seems to be there but Galaxy can't display the datasets.  Even if I create a new history and I run a tool the dataset is not shown. It is just displayed an error which says: "An error occurred while getting updates from the server..." and the details shows this: 

{
  "agent": "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/37.0.2062.120 Safari/537.36",
  "url": "http://galaxy.bric.ku.dk/history/view_multipl/api/histories/782c6cc7ec4cfd9f/contents",
  "data": "",
  "options": {
    "data": {},
    "silent": true,
    "parse": true,
    "emulateHTTP": false,
    "emulateJSON": false
  },
  "xhr": {
    "readyState": 4,
    "responseText": "{\"err_msg\": \"Uncaught exception in exposed API method:\", \"err_code\": 0}",
    "responseJSON": {
      "err_msg": "Uncaught exception in exposed API method:",
      "err_code": 0
    },
    "status": 500,
    "statusText": "Internal Server Error",
    "responseHeaders": {
      "Date": "Fri, 24 Apr 2015 12:09:40 GMT\r",
      "cache-control": "max-age=0,no-cache,no-store\r",
      "Transfer-Encoding": "chunked\r",
      "Server": "PasteWSGIServer/0.5 Python/2.7.3\r",
      "Connection": "close\r",
      "x-frame-options": "SAMEORIGIN\r",
      "content-type": "application/json\r"
    }
  },
  "source": [],
  "user": {
    "username": "jose",
    "quota_percent": 0,
    "total_disk_usage": 101352147,
    "nice_total_disk_usage": "96.7 MB",
    "email": "jjalmagro@gmail.com",
    "is_admin": true,
    "tags_used": [],
    "model_class": "User",
    "id": "72ad249754f05d26"
  }
}

Do you have any idea what could go wrong?

Thank you and best regards,

Jose