I ran the PPC Linux installer:
http://ftp.squeak.org/current_stable/unix-linux/Squeak-3.8-6665-powerpc-linu...)
and it worked but it had a bad side effect -- it changed the owner and group of several of the directories it touched to 1002, which is not a known user on my system.
This problem showed up later when I tried to log into gdm and couldn't because it could no longer write to /tmp which now had owner and group 1002. That's the simple explanation of the problem but it took me hours to research it and debug it.
Looking at the INSTALL program that comes with Squeak I don't see any reason why this bug would have happened, unfortunately.
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