For a moment, it looked as though the tarball didn't want to be unpacked as a non-priveledged user (i.e, not 'root'), but I tried it (granted, on Fedora 8, not Slackware) and it unwound and created the symlinks just fine.
Are you trying to unwind it in a dir where your user doesn't have full write permissions? Or, is the user your are logged in with restricted from running /bin/ln?