Notice: Undefined property: stdClass::$guid in feedapi_node_nodeapi()

line 51 of sites/all/modules/feedapi/feedapi_node/feedapi_node.module

According to http://feed2.w3.org/docs/rss2.html#ltguidgtSubelementOfLtitemgt I'll use the original url if the guid is missing.