Does this forum have an experienced Java Architect?  I would like to
bounce a few questions to someone with some industry experience.  I am
the project manager for a new software app. I would like some advice on
java architecture and technologies.  Appreciate this is all high-level,
but if certain technologies jump out to you then please let me know.

Scenario: Message brokering of news items over a LAN

User view is a java applet or could be java enabled web page (some kind
of smart console running on their PC desktop)

For now the application will have 50 users all on the same internal
network.

Central Oracle/SQL Server Repository - holding messages.

All clients communicate with central database that holds messages and
configuration information.

Based on the config. found each java client will dynamically build drag
and drop lists/trees of this information.

Ability to screen capture based on a user selection and upload the
image to a DB repository

Each client will be able to post new messages to the server which will
need to alert the other clients.

An author of a message can see if messages have been read by the
consumers.  If the user has not read the author can send a warning to
that particular user.

Licensing needs to be built in to restrict to 50 concurrent users.

Security login screens are required. Use central db server to
authenticate.

Scenario2: This is where it gets interesting.  How would this change in
a WAN scenario? - Could this even work using zero front print java?

Also if you live in/near London then please let me know.
Andy