/usr/local/src/xemacs/packages/src/xemacs-base-1.29-pkg.tar.gz ends up
installing the package in that ../packages/src/ directory instead of
../xemacs-21.2.9/packages/ making the installed package unreachable.
I believe ../packages/src/ was the current working directory when the
package-admin-add-binary-package was executed but the command should
have used a package hierarchy.
The same thing happens when trying to use the package-ui. I had to install
all of the packages by hand using tar.