[wusspuss]

It's not the lack of namespaces that causes people to reinvent them. Using or not using namespaces is a choice you take. With XMPP it's 100% dictated by the XML mindset. There is NO reason for

  <starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls"><required/></starttls>

to specify urn:ietf:params:xml:ns:xmpp-tls other than formalism/a yearn for bloat. There would never be a name collision without this ns and it convenes no useful info.

There's no reason for acks to specify urn:xmpp:sm:3 each time. Yes, here it at least specifies the version, but that's already negotiated when enabling acks anyway.

There's no reason why <query xmlns='urn:xmpp:mam:2' .../> can't be <mam_query .../>.

Namespaces are a choice, sometimes (e.g. in programming languages) reasonable, sometimes (in a serialization format for passing small texts around) not so much.

It is dictated by a mindset, the XML mindset in case of XMPP, and in the case you bring up apparently by the Java mindset, not to say there's much of a difference between the two

[EuAndreh]

> There's no reason why <query xmlns='urn:xmpp:mam:2' .../> can't be <mam_query .../>.

In this example, "mam_" is effectivelly a NIH namespace.