We had a bad experience with ejabberd pre-release version 3 (had an intern spend the entire summer on it, and I put some time in too):<p><a href="http:&#x2F;&#x2F;blog.fastmail.com&#x2F;2012&#x2F;09&#x2F;26&#x2F;one-step-forward-two-steps-back&#x2F;" rel="nofollow">http:&#x2F;&#x2F;blog.fastmail.com&#x2F;2012&#x2F;09&#x2F;26&#x2F;one-step-forward-two-ste...</a><p>Honestly Prosody looks the best.  We were planning to switch to it when async login support and scalability to thousands of domains was stable... but that was 2 years ago and it never quite materialised - and now DJabberd is so far behind in support for &quot;standard XMPP&quot; and the interoperability of the remaining servers that we just had to give up.  I argued strongly against it, having spent so many bloody years on making this thing work - including tons of patches to DJabberd and some EJabberd hacking as well - but the numbers didn&#x27;t lie.<p>Better to spend our time on exciting things like the currently-in-testing cross-domain support for Cyrus IMAPd and reverse ACL lookup that will make the LIST command blindingly fast even on big servers.  I&#x27;m hoping to be able to say two steps forward, one step back this time instead :)