[JDEV] Jabber and spam?

[Bart van Bragt]

I was adjusting my email spam filters, again, and that started me 
wondering about Jabber and spam.

IMO there are not many provisions to prevent spam from being 
sent/received in the jabber protocol. The only thing you can do is:
- block everything from anyone not in your roster except auth requests
- blacklist specific servers (very temporary solution)
- Filter on certain words/patterns (brrrrr, no a very clean solution)

I don't know of any clients/servers that implement the first 'solution'. 
Has this been though about? Any idea how spam can be prevented or at 
least reduced?

-- 
BartVB