XMPP/Jabber web client supporting conversation logging?

Question

I have an XMPP/Jabber account on www.autistici.org (they uses ejabberd). They don't log conversations on their server as GTalk does.

I need to use my Jabber account from a web interface hosted on my own server, but I want conversation logging. I've tried Jappix, but it doesn't have logging functions.

Any idea?

Otherwise, is there a way to log an external Jabber account activites on my own server? In this case the web interface logging abilities will not have so much importance.