Avoid Soft Links in Eclipse Headless build - or ant in general?

Ran into a really strange problem.

As a result of a headless Eclipse product build, I usually get an abc.app for Mac OS X.

But this time around I got an abc.app for Mac OS X that "worked", but the program icon was wrong. In addition, there was an Eclipse.app directory that's mostly empty.

Products for other architectures (Linux, Windows) looked OK.

Apparently, the build process had first put the Eclipse.app in place, tried to assign the icon etc., and then renamed it to the actual product name abc.app, but something failed in the process. The Eclipse.app partially remained in place, and there was no icon.

Solution: I had recently changed the build directory to /tmp. On Mac OS X, /tmp is a soft link (symbolic link) to /private/var. Either the Eclipse headless build or maybe ant in general has problems with soft links. After using a "real" directory path without any soft links as the build directory, things were fine again.