Unicode/character probs with 2.3.1 upgrade

What used to be very lovely International Phonetic Alphabet symbols (Unicode) on my blog have now turned into crazy nonsense characters since my 2.3.1 upgrade (using Fantastico). examples:

http://polyglotconspiracy.net/index.php/archives/2007/10/09/merger-prevents-discrimination/

and

http://polyglotconspiracy.net/index.php/archives/2005/05/13/validated/

I just noticed there are also a bunch of other funky A-type charcters showing up in random places, as well, as here:

http://polyglotconspiracy.net/index.php/archives/2007/08/10/making-mountains-out-of-hills/

Notice the A with tilde following most of the periods and in other places.

What in the world is causing this??? Any pointers are appreciated.