hi!
In Powerbuider, there's an example Distributed Applications into Code Examples, try to see it.
I have done applications where I can send commmands by a central program. All my applications send me a message telling me what they are doing...and for example, I can select an user and send him a message from my application.
I hope that it is all u need, i could do it with the example.
if u need help with the commands, please write me.
Regards.