AddThis Poor XHTML compliance

Using addthis v1.6.2 with WordPress 2.9.2 and run a W3C XHTML compliance test.
http://validator.w3.org/check?uri=http://blog.bottomlessinc.com&charset=(detect+automatically)&doctype=Inline&group=0

At least 21 or the 25 errors found were because of the addthis plugin.

Is addthis aware of this and working on making it better?

http://wordpress.org/extend/plugins/addthis/