Under Safari, after updating to a new version, I cannot log in at wp-admin as admin or any other user. When I submit accurate credentials, WordPress returns me to the login window. If I obtain a new password (using lost password), I still can't log in. The problem is specific to only some installations of WordPress (TeachEffectively.com; spedpro.org). It does not appear with a different installation (SpecialEducationToday.com) running on the same server.
The problem occurred on two different computers (both running OS X 10.5.4).
However, I can log in under Firefox.
When I log in under Opera, I get a security notice that reads as follows:
"A path in a cookie does not match the page address.
You might want to ask the site's Webmaster to set legal cookies."
The cookie name and content appears to be "wordpress_[randomCharacters]=admin%7c[moreCharacters]; path=/wp-content/plugins"
Removing comparable cookies from Safari's cookie list does not make it possible to log in. Removing all cookies associated with a site did not make it possible to log in.
I do not have the admin-ssl-secure plugin
Adding three secret pass phrases to the config file did nada for me.