This error means that another extension, plugin or template on your site is including Facebook's deprecated all.js Javascript library. That is the 'old' version of the Facebook Javascript API which was discontinued. It's no longer meant to be used and can cause conflicts with some JFBConnect features, as JFBConnect uses the recommended sdk.js library. This would cause the buttons to go missing as they conflict. Some common extensions that included Facebook features are JomSocial, EasySocial, K2. You specifically mention the Facebook Wall Feed extension, so I'd start to see if the all.js is included from there. When you find it, you can try commenting out the insertion into your page and check that the functionality returns for the wall feed and JFBConnect functionality works properly.
-Melissa
Conflict with another Facebook Extension
