I sent such a fix to wikitech-l yesterday...
I applied your patch and recompiled and installed Apache on my server. I changed my httpd.conf to add this:
RewriteRule ^/wiki/(.*)$ /wikitest/wiki.phtml?title=$1 [NE] RewriteRule ^/wiki/(.*)$ /wikitest/wiki.phtml?title=${ampescape:$1} [L] RewriteRule ^/wikitest/wiki.phtml(.*) /wikitest/wiki.phtml$1 RewriteRule ^/wiki$ /wikitest/wiki.phtml RewriteRule ^/wiki.phtml/(.*)$ /wikitest/wiki.phtml/$1 [NE] RewriteRule ^/wiki.phtml$ /wikitest/wiki.phtml
Using http://www.piclab.com/wiki works, so I know that rewriting is turned on. I updated the code from CVS. But I don't know whether or not it is doing what you expect. Can you please test it? If you've long since forgotten your login to my server, let me know).