Robot class,Keypress

we are presently working on a Java application using robot class. And we have used "keypress" method to send key to active window of application.

Its working fine on text-editor,browsers ,windows explorer,flash games,etc

but when we tried it on application like Turbo C,NFS(game),etc
it fails to send keys to such a non-frame application.

what might be the reason and can you suggest some other solution for this????

Thanks in advance.

does it sends key stroke to JVM and not to Windows OS???