Doing a little more digging -- if I right-click on a NoteTaker notebook (the
extension is .ntx incidentally, I am given the option to 'Show Package
Contents'. If I remove the .ntx extension, the icon for the file reverts to
a folder.
OK - so this is a 'package' as opposed to a regular file. I'm not sure what
a package is (other than a folder masquerading as a file) but I'll wager its
the reason why Entourage isn't showing it in its file list. A regular text
file with an .ntx extension shows up just fine.
Yes, that might do it. Packages are new beasties in OS X. Many things that
appear to be applications are really packages, "folders masquerading as a
file" as you put it. It provides a way to keep things together that must
stay together to work.
However, I think Entourage OUGHT to recognize aliases to packages. I'd
submit this as a bug via Help->Send Feedback.