I you're using 'Give Your Fonts Mono' (sprite font generator by Black Bee), you can add the characters you need, then generate the sprite font image.
For example, the charset below should be enough for most latim idioms and has russian charset too.
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789.,;:?!-_~#"'&()[]|`\/@°+=*$£€<>%АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯигрыабвдеёжзйклмнопстуфхцчшщъьэюяâçğıİîöşüûÂÇĞÎÖŞÜÛÁÉÍÓÚáéíóúÊÔêôÀàÑñÃÕãõì
You may add more characters depending on the languages you need.