Clean URLs don't work on test sites on a different port

This is most curious. URL path rewriting to allow clean urls (no ?q= in Drupal) work just fine on all the sites on the server except those that are accessed through the port that directs

I've checked out the rules in the sites-available configuration files and all of this is exactly the same.

Somewhere there must be port-specific rules that set up URL rewriting for the normal port 80 only?

I removed "Indexes" that followed Options and indented the Order allow etc commands, so that it looks identical to its live sibling, just a tad higher in the same file:

<Directory /var/www/drupal-5-2-test>
Options FollowSymLinks
AllowOverride All
Order allow,deny
allow from all
</Directory>

Now I'll try my old friend RewriteBase, which I notice I did set up our other installation of Drupal (5.1) to use. Curiouser and curiouser...

No, uncommenting and changing to   RewriteBase / in the .htaccess did not do it.

According to the WordPress forums there are all kinds of difficulties with different ports and mod_rewrite:

http://mu.wordpress.org/forums/topic.php?id=150&page

But Drupal expects to work on different ports, it's built into the multisite definition to be able to do so even with one installation.

This is most annoying. Will just use the regular installation on port 80 for now.

The Clean URLs handbook page did not help
http://drupal.org/node/15365

Resolution

This isn't solving the problem, but this is how we should do these rules, so we don't have to use .htaccess

Example Clean URL configuration of httpd.conf for performance
http://drupal.org/node/43788