X-plorer install error: can't find java

When running the X-plorer installer, I receive an error that it can’t find Java and to see the Read Me file. Has anybody seen this? The Read Me file does not mention anything of the sort.

I have tried several different machines, each with the latest Java installed properly and accessable from the command line (“java -version” works as expected), each running Windows XP SP2.

Please let me know if you have any suggestions.