oneguy on "[Plugin: Contact Form 7] Pressing 'shift' in captcha reset my form in firefox"

This is my site
Pressing 'shift' twice in the Captcha reset my form and delete all the data I have entered.
The form is on the right sidebar.
Do you know if it's a bug or that's the way it should be?
Thanks
Guy Lev

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