I have a file called RS232.java initially it did not belong to a package so I could simply do a javac RS232.java and then javah -jni RS232. Now I add the statement package bird; to RS232 and can no longer use javah. RS232 is in the directory bird and I have tried javah -jni bird.RS232 from 'bird' parent directory which is where I compiled this application. I also tried javah -jni RS232 from within the bird directory. No matter what I try I always get the error 'RS232: no such class' The whole application compiles and runs fine bur crashes when a native call is attempted.