If you use CGI's on your web pages (counters, etc.), then you've had to enable "shtml" processing in your httpd.conf file. Sometimes, though, you just want to stick a CGI counter on a plain boring HTML page. The standard solution is to rename the file with a .shtml extension so Apache will parse it. However, if you don't want to rename your files (as you'd then have to fix broken links from other pages), you can use the XBitHack flag in httpd.conf. Enter the following in your /etc/httpd/httpd.conf file:
XBitHack onThis directive tells Apache to treat any file that has the user-execute bit set as a server-parsed html document. So simply change the user 'execute' bit (chmod u+x filename.html) of any of the regular HTML files that you want parsed, and Apache will do the rest.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20011019010539630