Well, looks like this kills off my personal XMPP server - I don't think the software I'm using (djabberd) supports encryption for s2s connections and it's not really developed anymore. That's annoying.
Its been running for a few hours now without any obvious problem. I might have made some stupid error that makes the crypto entirely useless but considering yesterday it was all in cleartext anyway I think I can live with it ;)
Most of the XMPP server software out there is neither lightweight nor easy to configure and there's no real migration paths between them. I probably don't even have enough system resources on my personal server to run some of the more well-known servers anyway; they tend to be oriented towards deployment on large multi-user systems.
Yeah, was looking at Prosody. It's probably relatively simple in my case since I'm using the standard SQLite backends for roster storage etc. (Large-scale djabberd deployments likely aren't so lucky - djabberd was designed to make it easy for people to write code hooking in to their existing systems and many did. The only example I can find took a couple of months[1])
I wouldn't worry about system resources; if anything, I'd say that a high-level dynamic language adds most to the overhead. I can recommend http://ejabberd.im
