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That happens when the user can't do a stat() on the files (which requires execute permissions), but can read the directory entries (which requires read access on the directory). So you get a list of files in the directory, but can't get any information on the files because they can't be read. :) If you have a directory which has read permission but not execute, you'll see this. Someone probably tried to protect the .ssh directory incorrectly - it should be "chmod 0700 .ssh/" and owned by the user which owns the homedir. More than likely, someone was following instructions for securing a .ssh file but applied it to a .ssh directory. :)

If you do a chmod 0600 or 0400 on any directory, you can easily reproduce this behavior. Add execute permission to the dir, and it'll work fine.