Thanks for analyzing this and trying to find a way to make it work again.
I'm not sure what you did and I'm far from understanding how it works. But what I would really like to see is to use the "Apple recommended" way to build the installer. I would also make it easier to me to rebuild and distribute when there are changes.
https://developer.apple.com/library/...8447-TPXREF120

From what I read I would think the problem is the JavaApplicationStub distributed with Phex. I would be really happy if you could try to just replace the JavaApplicationStub with a updated one from Maverick.
This file should be located on your Maverick system here:
/System/Library/Frameworks/JavaVM.framework/Versions/Current/Resources/MacOS/

Basically I would like to know if Phex starts with the new Maverick JavaApplicationStub on Maverick and maybe also on older Mac OS X versions. Otherwise it may be necessary to provide two OS X builds.

Would be great if you could find this our for me. Thanks.

Gregor

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