I'm not really into Java at all, just sort of speaking off the cuff, but aren't there some compatibility issues between Java implementations? Mainly Microsoft's Java and Sun's Java. This may not be any sort of issue with what you are describing, but I have seen something of the sort cause problems in the past. Mainly, a Java app (using Sun's Java) not playing nice with MS's Java when we attempted to run the app on a server (so it wouldn't be tied to a workstation). Ended up we had to run it off a workstation where Sun's Java could be loaded. Just sort of tossing out my 2¢. :-)
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