While modern systems (on server and client side) work quite well with non-latin (UTF-8) URLs, they still present some technical risk. Transliteration of cyrillic URLs to their latin representation can be accomplished quite easily with the standard umbraco URL-Replacing in "umbracoSettings.config" (in directory "/config/").

It is not possible to account for some of the finer details, but using a simple replacement table will handle 95%+ of most document URLs. Here's the list to insert below the already existing "char"-Items inside the urlReplacing-Tag:

<!-- GOST 7.79 transliteration for cyrillic characters -->
<char org="">A</char>
<char org=""></char>
<char org="">B</char>
<char org="">b</char>
<char org="B">V</char>
<char org="">v</char>
<char org="">G</char>
<char org="">g</char>
<char org="">G`</char>
<char org="">G`</char>
<char org="">g`</char>
<char org="">g`</char>
<char org="">D</char>
<char org="">d</char>
<char org="">E</char>
<char org="">e</char>
<char org="">Yo</char>
<char org="">yo</char>
<char org="">Ye</char>
<char org="">ye</char>
<char org="">Zh</char>
<char org="">zh</char>
<char org="">Z</char>
<char org="">z</char>
<char org="">I</char>
<char org="">i</char>
<char org="">J</char>
<char org="">j</char>
<char org="I">I</char>
<char org="">i</char>
<char org="">Yi</char>
<char org="">yi</char>
<char org="">K</char>
<char org="">k</char>
<char org="">K`</char>
<char org="">k`</char>
<char org="">L</char>
<char org="">l</char>
<char org="">L`</char>
<char org="">l`</char>
<char org="">M</char>
<char org="">m</char>
<char org="">N</char>
<char org="">n</char>
<char org="">N`</char>
<char org="">n`</char>
<char org="">O</char>
<char org=""></char>
<char org="">P</char>
<char org="">p</char>
<char org="">R</char>
<char org="">r</char>
<char org="">S</char>
<char org="">s</char>
<char org="">T</char>
<char org="">t</char>
<char org="">U</char>
<char org="">u</char>
<char org="">U`</char>
<char org="">u`</char>
<char org="">F</char>
<char org="">f</char>
<char org="">X</char>
<char org="">x</char>
<char org="">Cz</char>
<char org="">cz</char>
<char org="">Ch</char>
<char org="">ch</char>
<char org="">Dh</char>
<char org="">dh</char>
<char org="">Sh</char>
<char org="">sh</char>
<char org="">Shh</char>
<char org="">sht</char>
<char org="">A`</char>
<char org="">``</char>
<char org="">Y`</char>
<char org="">y`</char>
<char org="">`</char>
<char org="">`</char>
<char org="">E`</char>
<char org="">e`</char>
<char org="">Yu</char>
<char org="">yu</char>
<char org="">Ya</char>
<char org=""></char>
<char org="’">'</char>
<char org="">Ye</char>
<char org=""></char>
<char org="">Fh</char>
<char org="">fh</char>
<char org="">Yh</char>
<char org="">yh</char>
<char org="">O`</char>
<char org="">`</char>
<char org="">(No)</char>

Maybe this is of use for someone. I also hope, the forum editor will handle this characters well ... ;)

Remember to reload the umbraco config (i.e. by touching the web.config in the root) after applying!