GamingPlanet on "[Plugin: Contact Form 7] Send button does nothing"

Hello,

We are trying different Contact forms to replace our old one.
In 1 page i'm trying Contact Form 7 as widget text, but the send button does nothing, no error or other message is shown.
The contact form is on https://perfectbackup.nl/partners/partner-informatie/

The entire site is forced on SSL, maybe this has something to do with it ?

http://wordpress.org/extend/plugins/contact-form-7/