talk <username> always goes to the answering machine. Why?

I get the following message whenever I use the talk command:

$ talk shashi
[Connection established]
Hello. You're connected to a talk answering machine.
The person you have paged isn't there at the moment.
Please leave a message and quit normally when finished.

I even tried to include the ttyname but it still went to the talk
answering machine!
$talk shashi /dev/pts/7

Can anyone please explain why this could be happening? What do I need
to look for?

Environment: Redhat Enterprise Linux ES 4.0; talk-0.17-26

Thanks,
Shashi