New Safari update notes:
afari 5.0.2 Software Update:
This update contains improvements to compatibility and security, including the following:
Fixes an issue that could prevent users from submitting web forms
Fixes an issue that could cause web content to display incorrectly when viewing a Google Image result with Flash 10.1 installed
Establishes an encrypted, authenticated connection to the Safari Extensions Gallery
For detailed information on the security content of this update, please visit this site:
Apple security updates
This just showed up on my mac tonight, so this may fix your issue (if on mac, check for win).