[Plugin: Grunion Contact Form] Fatal error: Call to undefined function akismet_http_post()

I got this error on my test site (which has search engines blocked and doesn’t have Akismet installed):

Fatal error: Call to undefined function akismet_http_post() in /home/username…/test.cliffpaulick.com/1/wp-content/plugins/grunion-contact-form/grunion-contact-form.php on line 497

This was my code:
[contact-form to="[email protected],[email protected],[email protected]" show_subject="yes"]

I also tried this and got the same error:
[contact-form to="[email protected]" show_subject="yes"]

NOTE: email addresses changed (i.e. not actually what I entered in my code)

P.S. I didn’t see any “Settings” page within the backend.

Thanks for this plugin. I’m hoping to get it working soon! ??