hi friends

is it possible to implement system like communicaiton systems,
idea is that;
i have about 60 clients and one server. All clients checking messages. All mesages comes server firstly then it will redirecting to client(user).
Up to here no problem for me.
is it possible to trigger client computer as you have new message?
But i dont want to use a thread to check on initaliazed time interval as 5 min.
when mesaage is come triger to client computer.

is there any one to have idea for that?
Thanks..