If the yahoo groups interface has a "chat portal"  that would be the best choice, so that users aren't required to get new logins beyond their existing Yahoo Groups powderworks login.
There was another French user about 6-12 months ago.  He's been quiet for a while.

winnie le pinguin wrote:

hi all,
 
tell me, could we chat together on the yahoo chat ?
we can chose a date and an hour for the beginning and talk together all we are
no ?