mount not working for utf-8
URL-encode the server name:

Προκρούστης &gt; %CE%A0%CF%81%CE%BF%CE%BA%CF%81%CE%BF%CF%8D%CF%83%CF%84%CE%B7%CF%82


The quotes aren't required here, so the following should work:

mount -t smbfs //%CE%A0%CF%81%CE%BF%CE%BA%CF%81%CE%BF%CF%8D%CF%83%CF%84%CE%B7%CF%82/DiningRoom /Volumes/DiningRoom