I get the following JS error in IE when trying to dynamically load comments plugin.
'null' is null or not an object
dynamic comment loading plugin works fine in Firefox, Chrome, Safari and Opera, but throwing the above error into the whole version of IE (not tested on IE9)
Example page - http://dl.dropbox.com/u/3804052/fb-comments-test.html
In the example page above, click "click me to check the dynamic loading of facebook comments plugin" and you can simulate the dynamic loading of comments plugin and notice the error in IE6 / 7/8
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