I am getting something very odd happening with IE9 (what a surprise!)...
I am using silverstripe 2.4.5 / UserForms Module
This is the page that is causing issues... http://www.funcup.co.uk/entry-forms/rental-driver-entry-form
Works perfectly well in Chrome, FF, Safari, Etc. However in IE9 when you submit the form it gives me an HTTP/400 error, which I can only presume is because it hits the 4000 character limit on the maxpost size of IE?
Has anyone come across this yet, or indeed how to get around it?