Too bad no one is interested in fixing this. I guess they went AWOL
PM's code base dates back the 1990s. http://everything2.com/title/Everything+Engine
Granted, some of the issues with code tag processing could have been dealt with in the early days of PM, however, the limitations of the windows-1252 character set did not become a problem until years later.
Unfortunately, getting the PM website to handle Unicode/UTF8 is much more complicated than adding use feature 'unicode_strings'; statements to the code.