I see. I have no clue about facebook, mobile or not. It may be as close as
you are likely to get, if you want to use facebook. You can still be freer
and not use it.
The fb chat is not xmpp. From facebook developers page:
"Facebook Chat should be compatible with every XMPP client, but is not a full
XMPP server. It should be thought of as a proxy into the world of Facebook
Chat on www.facebook.com. As a result, it has several behaviors that differ
slightly from what you would expect from a traditional XMPP service:
-Your client cannot send or receive HTML messages
-Because roster items and presence subscriptions are based on the user's
Facebook friends, they cannot be created or deleted using the standard XMPP
mechanisms.
-Facebook Chat is terse when sending updates for new friends, because the
negotiation happens outside of XMPP. Future versions of Facebook Chat may be
more conformant.
-The user's own Jabber ID (JID) is different from the Jabber ID that their
contacts will see because the translation is done internally.
-Arbitrary IQ stanzas cannot be passed between clients.
-Presence probes do not currently work.
-Non-SASL authentication with the jabber:iq:auth namespace as described in
XEP-0078 is not currently supported.
The XML parser does not yet fully handle XML namespaces. Please stick to
the same style as the examples in XMPP RFCs 3920 and 3921 when using XML
namespaces."
The most important deficiency being you're either stuck inside their walled
garden, or out. I wonder if at least it gives you the chance to use OTR?
