Problem with MailChimp plugin and Membership plugin


I've got both Membership and MailChimp plugin on my site so that I can offer a MailChimp signup form to a newsletter list and also to automatically add new subscribers.

When a new user signs up, the MailChimp plugin throws an error as the Membership subscribe form does not ask for a FNAME and SNAME which is what the MailChimp plugin seems to want.

When I deactive the MailChimp plugin it goes through OK.

I really want these two plugins to play nicely together. Is there any way I can switch off the required FNAME and SNAME fields for MailChimp, but even better still, can the First and Surname fields be added to the Membership subscribe form. Kind of surprised it doesn't ask for that on sign-up...