The Problem: all of the styles have morphed into a style called "default
paragraph font para char"

Have a major document (MS Word 2003, Professional version / OS is Win XP)
that will need editing, etc for the rest of its long life. Created styles for
it that worked like a charm. Finished/published it 2 weeks ago. Looked at it
today and every style has morphed into a strange style called "default
paragraph font para char" that I've never seen before. However, the doc still
looks exactly the same as before. Several of my backups/revisions have the
same problem. None of my other documents have this problem.

I've never seen such a thing. Microsoft Knowledge Base has no clues for me
(that I can find). What happened? What can I do?