Java APIs

Hello fellahs, as the title of this post says I'm making a client and server application. The server are supposed to handel several clients, and the communication is done true UDP.

I have got two questions concerning this. The first one is if a exception is throws in the server should I then send the exception back to the client in serialized form. If I choose to do this then I also would need to handel the exception classen to the client. Or should I send back a regular IOException and use it's init cause to define the exception which occured in the server.

The second question is concerning the multi client support. If this is going to work then I would need to time-out the connection i the server environment, and I have not a clue about how long it should be?

/thanks in regards Ali.