ajc is using the wrong JVM. How do I fix it?
The easiest way to fix this is to re-install ajc (using the same .class or .exe file that you originally downloaded) and this time make sure to tell it to use the desired JDK (typically the JDK versions 1.2 or 1.3 from Sun). If you are familiar with DOS batch files or shell programming, you could also fix this by simply editing the bin\ajc.bat or bin/ajc script.