follow the link I posted above and it tells you exactly what to do
I had the same exact error message until I removed the plugin.
PHP Version: 5.2.17
Wordpress version: 3.3.2
Theme: Cloriato Lite
widgets are supported and I am using the CafePress and Image (Jetpack) widgets now
Plug-ins:
Awesome Flickr Gallery
CafePress Widget
Embed PDF
Event Registration
Google Analytics for WordPress
Jetpack
Mailchimp
W3 Total Cache
I have not noticed any problems with my site after deleting the plugin. I guess I was lucky.
I had the same problem. Solved it by following the instructions here to disable the plugin
