I am loading all articles with Ajax but Addthis functionality is not correct
$thisChild.load( permLink + \' #thePostStuff\', function() {
And
I wrote a pretty detailed description here https://stackoverflow.com/a/16950881/1118070 but, the gist is that addthis.toolbox(".addthis_toolbox");
is the correct solution, but it's important to note that it should be called each time the new ajax content is loaded.
html
javascript
// onload of the ajax content
addthis.toolbox('.addthis_toolbox');
Also note that anything that loads as an iframe such as the facebook like counter, it will cause problems if it is nested within a '.addthis_toolbox' container. I'd suggest putting it inside it's own container and calling the toolbox() method on them both.
See my link for more details.