Sun provides JVM for Linux, Solaris and Windows. The JVM for the otheres OS usually are provided by the company that makes the OS: Apple makes the JVM for Mac OS, for example. So have a look to the website of company that make the OS.
Abraham Otero,
http://people.javahispano.org/~abraham/
Thank you all for the reply. I have noted regarding jvm for OS390. Trouble is we have > 30 banks where this application has to be installed and run and these are very old systems like nsk and ve. so this would mean we need to have the jvm for all the different OS running. i would collect more info on the various OS before deciding if it can be done in java.