How odd. I never saw that before but now I am getting it on my site.
I was able to resolve the problem for the moment by adding the following replacment variable to my templates
replace with
Code:
<html xmlns:fb="http://www.facebook.com/2008/fbml"
Temporary fix I think, but it cleared it up on my site.
My idea for using template hooks for the login buttons is not working out well. There are no good hooks in Navbar.I will see what other options I can find.