Downloaded 3.0 upgrade / site and login crashed

I recently downloaded the latest version of WordPress (3.0).

Immediately after I downloaded this my web site crashed and I have been unable to access the login page to get to the Dashboard.

Here is the error message now appearing on the site: Fatal error: Cannot redeclare is_rtl() (previously declared in /hermes/bosweb/web022/b223/sl.culpeper/public_html/wp-includes/locale.php:347) in /hermes/bosweb/web022/b223/sl.culpeper/public_html/wp-includes/locale.php on line 349

If someone could let me know what to do, that would be great. My e-mail address is [email protected] if you would prefer to e-mail. Thanks.