named namespaces not handled resulting in errors

The xml parser in libjabber does not handle named namespaces properly. For example, this unnamed namespace is handled correctly:

<query xmlns="jabber:iq:roster">

But this named namespace is not:

<ros:query xmlns=”jabber:iq:roster” xmlns:ros=”jabber:iq:roster”>

This breaks functionality with servers that return valid xml with named namespaces (e.g., Google Talk, on which the roster is not available to mcabber due to this bug).

Bug in Loudmouth (0.10.1 doesn't use libjabber anymore), already fixed in development branch.

Duplicate of #86.