Nicholas, I just found out that it seemed to be a conflict with my theme. I am using Nonprofit by Organic themes. I switched back temporarily to Twenty Eleven and everything worked great. If your’e not currently using Twenty Eleven theme you might want to try switching to it to see if that will resolve the problem.
Nickolas, I am having the same trouble with my site. I have tried various emails and browsers but I never get a confirmation email. Did you ever resolve this problem?