FULL PRODUCT VERSION :
java version "1.6.0-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-rc-b69)
Java HotSpot(TM) Client VM (build 1.6.0-rc-b69, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

EXTRA RELEVANT SYSTEM CONFIGURATION :
Configuration of this application:
RMI based capture screen server which captures screenshots. It is run as a windows service which has "Allows service to interact with desktop" option checked.

A DESCRIPTION OF THE PROBLEM :
Robot when running as a windows service can't capture the REAL user screen in the following situations:

1) when the windows log on screen appears
2) when the user perform a SWITCH USER to log on with another user
3) when we enter text mode (like starting command prompt and pressing alt+enter)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
The application works if you perform the following scenario... start client (it receives images from rmi server - the result is OK). Log off windows user. When you log off user the robot captures just a BLACK SCREEN(in this case the result is WRONG). If you log on with another user the Robot captures again what it should capture(the current screen which is seen by the user) - so now the result is OK.

The last scenario fails when we perform a switch user. So... the scenario is like this:

Log off from all accounts.
Log in with one user... start the capture client(the result is OK)
Perform SWITCH USER (user now sees a BLACK SCREEN - the result is WRONG)
Log in with another user (when the new user is logged in, it still receives BLACK SCREEN - result IS WRONG)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I am expecting that Robot should capture the screen that I see in the switch user situation, in the log on screen and in text mode
ACTUAL -
just a black screen as an expected result

REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
i think a solution for the switch user (i mean when the second user is logged in and receives a black screen) is to check if robot captures the correct "Window Station" as it is called by Microsoft documentation at this address:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/window_stations.asp

but... i don't think this is a solution for the log in screen.