I meant to say there that the last version (and the previous one, 2.2) is not for ATmega8, since all other previous versions were also applicable for ATmega8, too. The version 2.3 needs Flash > 8KB. It can be used on controllers having RAM and flash bigger than that (1KB RAM and 16KB flash onwards).
Thanks for showing that confusing sentence, I've removed now the "only" word from it and also added a small note.
EDIT: 1KB RAM (by mistake, I had mentioned it as 2KB)