While I was implementing JID Escaping I came across an inconsistency. It is easy to see that it wont work as a 1-to-1 mapping for general JIDs since the presence of the "@" and "/" characters to be esacped makes it impossible to uniquely decompose a JID into its node+domain+resource constituents.
With User Activity I don't mean my own activity (low) but the XEP-0108. This is one in a line of XEP's that relies on the PEP XEP. Since it relies on PEP it is normally an easy task to implement the client side of it. Now in Coccinella cvs.