As you may know, my company offers the most popular robots.txt generator in the world free to visitors, and we are continually adding functionality.
In response to a recent request, we've added Naver to the robots.txt tool. Naver is the most popular search engine/portal in Korea. I've been to Korea several times, and (because it's my job) I always ask everyone I meet what search engine they use. It's almost always Naver, and there is good reason for it.
There is one thing I've learned doing international SEO - the Koreans are really, really good at creating useful and engaging web content. Some of the best free online games, tools and services are Korean. Google is getting their proverbial butt kicked there, and it's because they simply are not good enough. I still honestly think that Google got the idea of universal search from Naver - Naver was doing it long before Google was, and is still doing it better.
As a result, I'm kind of surprised I hadn't added Naver to the robots.txt generator already, but I guess it's better late than naver.... ;)