ISO talk-like utility

[<kynn@panix.com>]

Hi!  I am looking for a simple utility that would enable users to send
simple messages to the tty of another user currently logged on
(e.g. "your job # 12345 is slowing down the system!").  The purpose is
to communicate urgent messages for which e-mail may be too slow (since
with e-mail, the communication happens only when the recipient chooses
to read his/her mail).

In other systems that I have worked on there was a command "talk" for
this sort of thing.  What is the standard utility in Debian systems
for this sort of thing?

Thanks!

kj