rich snippets: missing field "updated" and hcard "author"

hi, i get following errors using googles rich snippet test tool. Warning: Missing required field "updated". Warning: Missing required hCard "author". errors in hatom-feed for a wordpress page url and only Warning: Missing required field "updated". error in hatom-feed for a wordpress post url How to fix it. Please help!! hatom-entry: (entry-title, entry-content) is absolutely fine. i found some tutorials to fix this and they are all about changing single.php and they all do not work... can someone help? it would help many people.. i found a few threads without an answer to this specific question!