Fatal error on new user registration to the site

Hi,

I just installed all the simplenews modules and when I tried to register a new user for testing puropses, I got this error as soon as I clicked on the register link:
Fatal error: Call to undefined function _simplenews_get_vid() in /hsphere/local/home/carta/cartamagica.com/events/sites/all/modules/simplenews_register/simplenews_register.module on line 85

Please advise