Melder, I had that problem too (of HTML breaking). When I installed a fresh 6.2.1.1, and rehacked with the current calendar hack, the problem went away. Seems like something's really fragile there, but it does show that it's not a problem with the hack. Not really sure.
I've been looking over these posts and I'm curious...do the birthdays automatically update themselves now? I had to do the same thing as guvner - manually edit EVERY member profile myself to get the birthdays to appear on the calendar. (And I have over 280 members). I did make a post about this not too long ago - is there something in the control panel now that puts the birthdays on the calendar automatically? That wasn't made clear to me.
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