How to include PWD into hardstatus line?

[Rusty Shackleford]

I tried adding $PWD to my hardstatus, but that seemed to store the
initial directory and not update as I moved around.  I couldn't find a %
symbol for the current directory.

Also, sometimes I start a screen on host XXX, then rsh to another host
YYY, but the screen hardstatus still displays hostname XXX and cpu load
average info for XXX.  Is it possible to update that to YYY's hostname
and load average?

TIA