Report the asshole and stop bitching about it. And it is funny, cause it happened to you.
Reporting it would do little since he's A) using multiple proxies to spam (probably other people's computers he's hacked) so he has no static IP address to track, and B) he was posting under anonymous. Livejournal wouldn't be able to do anything if he has no account.
In repsonse I've locked anonymous commenting.
In response to that, he makes a LJ accountNow I can do something about him. I've already banned that account from being able to touch my journal. However, he might make other accounts and try to spam with them, in which case I WILL be able to complain to Livejournal's staff. LJ will only take my complaint seriously if I've exausted every means of trying to stop him from spamming.
And to those who think this is funny, realize that these G * N * A * A people, as well as other trolls, hackers, script kiddies, and cockroaches of the internet could spam this board as well. Since Anon commenting is on, first he'd spam under anonymous. IP banning would fail because he has proxies. If you turn off Anon posting, he would make multiple accounts and spam with them. You could try deleting the accounts but he might make new ones as fast as you delete them. The only way he'd go away is if it was extremely difficult for him to spam anymore, like if Nuri locked down the board and prevented any new accounts from being formed.
Trust me, I too have gotten around bans at boards. None of those times were to spam them though. I'm not that lame.