Short version: if you are an international user and pick English as your forum language (in your profile), phpBB serves all pages as ISO 8859-1 and cyrillic characters render as garbage unless you change your browser's settings.
Long version:
Anyway, the problem is/was this: all cyrillic characters in the forum show up as garbage characters to me. Actively setting my browser to interpret the forum as a Russian character set worked perfectly, but for a friend of mine it always worked right from the start. His browser picked the right character set all the time, every time. But not mine.
Today I edited my profile a bit, and realized the cause: I've selected to have the forum in English. That's good, since it enables me to read the menu options
... However, phpBB apparantly sets the character code of the page according to your chosen language. Which means that once I picked English phpBB started setting the character code to ISO 8859-1 for all pages.And boom!
Garbage characters instead of nice cyrillic ones.
