What is known in US and what is known in Europe is of course different, then there is even what is generally known in each contry.
For example name Lalli is medieval name, it is not english name as is not name of topic starter's character, but for me it is bit unclear if such name is allowed or not?
This is quite widely known legend in Finland, but most likely as unknown in US as legend of topic starter's character name.
http://en.wikipedia.org/wiki/LalliThese can of course make some not wished effects in game and I believe such names should not be used because of that. Of course it is quite impossible to know all these things and there is no way GMs or Moderators could know everything, but this might be good guideline for choosing name in instrucitions so new players could be aware of policy. Of course if this is taken to policy.
I believe issue will come up more often in some distant or not so distant future, when there is more players from different countries.