This might be a dumb question. How to determine if Broker_API_Java_6-5-2_Fix2 has been installed or applied on the server?

Check the WmBrokerAdmin package in admin console. You may get that info here.

Cheers
Guna
http://sekkhaar.blogspot.com

Here is how you can:

1. Go to /lib
2. Get the wmbrokerclient.jar file
3. Extract the file in some other directory
   jar -xvf wmbrokerclient.jar
4. Navigate to COM/activesw/API/client in the extracted directory.
5. view the version.properties file
6. VersionLabel gives you the fix level. (Fix2 actually shows as Fix3 due to PS error).