Is this legal? A lot of private servers where you aren't supposed to host (ie, RS, not wow). Its not on http://iro.ragnarokonline.com/download/download.asp so I really doubt it.

According to the Ragnarok website, it is an imediate account deletion if you are found to be the owner/operator of a private server. See http://iro.ragnarokonline.com/support/operationrule.asp for more information on bans.
-jimmy

Well, just because they say it's grounds for account termination in the TOS, that does not make it illegal in terms of what you do in the real world. Here's thie thing...private servers have always been a bit of a legal grey area. The dicklicks over at Gravity can terminate your account for whatever reason they want, they don't need a reason at all, it's a private service. The only time that operating a private server is for sure illegal is if you're using the stolen and hacked Aegis server which Gravity created. If you're running a server using jAthena or eAthena (both emulators) you aren't doing anything illegal unless you're profiting off the server (abuse of trademark) or selling a service. In fact, the people connecting to your server and those distributing your patchfiles is who the Gravity people are going to send takedown notices to.