I'm unable to use the contact form on the Author's site (maybe they have a similar issue ;)
I've just installed business directory plugin Version 0.8.4 Beta
My WordPress version is 2.8.6
It activates ok but when I click on one of the Submit buttons for either the Add Business form or search form it does nothing. When I view the console in Firebug it says 404 page not found, I think it's unable to locate requests.php.
I tried editing business-directory.php and changing the path for requests.php to an absolute path etc but this did not fix the problem.
I've also tried deactivating all plugins (apart from this plugin) and changing the theme to the default WP theme but still the same problem. As well trying with non-permalinks.
The website says the plugin works with 2.8.5 so I assume something new in 2.8.6 is causing this to happen?