Java problems on os X

I am trying to use the Java Front Panel API (v3.0.11) with my mac (running 10.5.8) with the Eclipse IDE but I am getting the following error;

Exception in thread “main” java.lang.UnsupportedClassVersionError: Bad version number in .class file
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(
at Method)
at java.lang.ClassLoader.loadClass(
at sun.misc.Launcher$AppClassLoader.loadClass(
at java.lang.ClassLoader.loadClass(
at java.lang.ClassLoader.loadClassInternal(

From what I can gather, this error is caused by the mac JVM being 1.5.0, whereas the API has been compiled with JVM 1.6. I have also read that Eclipse on mac only works up to JVM 1.5.0, so I don’t think it is possible to upgrade to 1.6 to try and solve the problem.

Is it possible to get the Java API (the jar and the lib) compiled with 1.5.0 to ensure compatibility with Eclipse on OS X, or is there another solution that could solve my problem?

Thanks in advance,