Ejabberd is the best XMPP server that can tested. But i have a little suggestion. I think that Groups can be created in datase and then assign to specified service.
Example:
Some Users can use s2s or Yahoo transport.
Many others examples can merge. The idea is a table like user group .. then in the ejabberd,cfg
{yahoo , {[Admins,[YahooAllowed]]}}
Thanks.
PD: WHEN 2.0 FINAL ?
