STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. install 6u18_b05 on windows
2. import a jaws application into user cache, for example:
javaws -import http://sqeweb.sfbay.sun.com/jsn/users/fred/reproduce/defaultSystemCache/defaultSystemCache/html/UserThenSystemImport.jnlp
3. import the same jaws application into system cache, for example:
javaws -import -system http://sqeweb.sfbay.sun.com/jsn/users/fred/reproduce/defaultSystemCache/defaultSystemCache/html/UserThenSystemImport.jnlp
4. open java cache viewer via java control panel.
5. check "Applications" and "Resources" view
6. check "System Applications" and "System Resources" view
7. check "Applications" and "Resources" view again

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The application and relavent resources are only in system cache
ACTUAL -
Applications and resources are also in user cache in step 5
In step 7, no application is in "Application" view. Sometimes, some resources are still in "Resources" view

REPRODUCIBILITY :
This bug can be reproduced always.