Rewrite problems

[godsbluehills]

Not sure if this is a Drupal problem or an Apache problem. I just reinstalled xampp (newer version) due to a mysql privileges issue. Now I'm having a very strange rewrite issue. For some of my virtual hosts, the home page rewrites to local.url.com/xampp/index.php. So Drupal returns a 404 error. This only occurs on the home page, as far as I can tell. All other pages are served up correctly. It doesn't matter whether or not clean-urls is enabled. I've tried removing .htacess from the virtual host root and it still redirects to local.url.com/xampp/index.php. So this leads me to believe it's an httpd.conf issue. Here's what's weird:

* If I access the domain through a .org address, everything works fine. So for example, one of my virtual hosts is local.mtlandman.com. This url returns local.mtlandman.com/xampp/index.php, but when I set up a virtual host for local.mtlandman.org (same settings), it works perfectly. .com and .net address seem to have problems.
* If I add a variable to the url, it works perfectly, even if the variable doesn't exist. So local.mtlandman.com?p=blah or even local.mtlandman.com? works fine. So the variable seems to "escape" the weird xampp rewrite.
* The issue only occurs for drupal sites. I have other sites that also use index.php files and custom .htaccess files, but none of these sites have the problem.

I hope this all makes sense. Please let me know if I need to clarify. I've been pulling my hair out for the last 15 hours trying to figure this out. Tried reinstalling xampp, modifying .htaccess, httpd.conf, http-vhosts.conf, php.ini, but nothing seems to work. I'm definitely no apache guru. Xampp is version 0.7.1 on Mac Leopard. I tried php4 and php5, and I blew away my databases and started from scratch, but got the same problem. Thanks in advance for any insight.