Some notes about revisions

Packet Relay support

On XEP-0033, section Discovering Server Support, it says: 'The server MAY choose to limit whether non-local servers can send address headers that require the local server to send to third parties (relaying).'

Packet relay does not seem such an important feature. This feature must be explained with more detail, and make it optional both for implementation and deployments.

Proposed changes related to packet relay:

it needs to be specified more clearly: what is packet relay?
describe all this on a separate section, for example: 6. Packet Relay
packet relay is not a required feature on software
it is an optional feature
server devs may implement it (disabled by default), just in case somebody wants to use it
usage of relay on XMPP network is discouraged. right now the spec says you SHOULD allow relaying (since you MAY decide not to allow it). Let's change the wording to discourage relaying (SHOULD NOT allow relaying)
specify more clearly when relaying might be allowable (e.g., if there is trust between the servers) because otherwise this could be abused

http://badlop.blogspot.com/2007/06/packet-relay-no-thanks.html

MUC logs

Don't send multicast packet to replyto and replyroom

This may seem obvious, but it should me explicitely mentioned somewhere on the XEP: the destinations that the multicast service should send the packet are the ones with TYPE=TO or CC or BCC, and DELIVERED != TRUE. This means that replyto and replyroom addresses are not destinations of the packet at all.

Multicast Usage: don't require to check delivery

On XEP-0033, section Multicast Usage, it says: 'The server checks to see if it can deliver to all of the specified addresses. If not, the stanza is returned with a "Forbidden" error, and processing stops.'

This step should be completely removed, since it would require a lot of work and delay on the server.