subscribe by email javascript error

I noticed a javascript error on our site: http://ukmarketingnetwork.com. I have taken the plugin out of the mu plugins folder, until I can get this sorted.

I disabled all plugins and started testing. It seems to be subscribe by email is causing this error. When I have it in mu plugins (all other plugins disabled) by itself the error still occurs.

I am using Buddyprss Corporate 1.3.1, WP 3.0.1 and BP 1.2.6

The error is: element.dispatchEvent is not a function Line 4619