The site is redirecting just fine.
You said:
I have recently moved my wiki from http://www.knitting-and.com/wiki to http://www.knitting-and.com/w and
want
the entries to still show at http://www.knitting-and.com/wiki
They are and all short URL work fine. I am guessing from your original statement, you changed directories.
http://www.knitting-and.com/wiki/Main_Page and any short URL I browse to.
I believe you're thinking wiki/index.php?.... instead of w/index.php?....
Since you changed your directory from /wiki to /w, the long URLs are now...
http://www.knitting-and.com/w/index.php?title=Main_Page and it works just fine. /wiki is a rewritten fake directory now, it doesn't really exist.
If you call /wiki/index.php?.... whatever, anything after the ? is truncated and index.php shows up as a 404, uncreated article. This behavior is correct. Rewrite is parsing and preforming correctly as far as I can tell. Even &action=edit shows me the source of a page.
Tom