JavaScript throwing sun.misc.InvalidJarIndexException: Invalid index

Question

I'm trying to run a importPackage call in JavaScript code that I'm invoking in my application and it's throwing a "sun.misc.InvalidJarIndexException: Invalid index" exception.
The exact line of code that's throwing the exception is:
importPackage(com.mathworks.toolbox.javabuilder);
This works fine when I run my application in Windows XP, but now that I'm trying to run it in Windows 7 64-bit it's not working. Another weird thing is that if I try to import any other packages that have the "com" prefix I get the same exception, I'm not sure if this has anything to do with it or if it's purely coincidental. I have other imports with out the "com" prefix that work just fine.
Has anybody ever seen this before?
Thanks for the help.

Answer 1

Found it!
jfxrt.jar was conflicting with the imports. I don't know why, but removing it from the classpath solved the problem. Maybe it was jfxrt.jar's INDEX.LIST file. I'm going to dig a bit further...