Try manually resetting your plugins. If that resolves the issue, reactivate each one individually until you find the cause.
If that does not resolve the issue, access your server via FTP or SFTP, navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the Default theme (WordPress 1.5 – 2.9.2) or the Twenty Ten theme (WordPress 3.0 and higher) to activate and hopefully rule-out a theme-specific issue.
yeah, i did the same thing you tell and find out the plugin and fix it.
