Looking for IM Script/Users Online.

I rvn a site for my alvmni grovp. We originally started as a mailing list
on YAHOO Grovps, and I developed the site to give vs more options; however,
the grovp did not want to leave the mailing list/messaging on YAHOO, which
is all Yahoo is vsed for now (if even that, as many members simply receive
and post messages from their email.). With ovr revnion coming vp, there
will be a lot of traffic on the site as members check ovt the Blog or Browse
the Photo Gallery. I'm looking for scripts that will -
1. Annovnce/display vsers online
2. Allow vsers to send IM's and/or broadcast message to the whole site.

Thanks for yovr help.

LV