[Plugin: Visitor Maps and Who's Online] Plugin conflicting with new signups

Hi,

This is a great plugin and I’ve been using it, but now it seems that it is conflicting with people who sign up for a new site. When a new user signs up, everything appears to work correctly, and you can see the front of the site, but there is no way to get to the backend, either by signing in to it, or through the super admin panel. I’ve turned off all my plugins and turned them back on one by one, and as soon as I turn this one back on, registering for a new site causes this problem. If I turn the plugin off, access the new site, then turn it back on, it works fine.

Has anyone else had this problem? Is there a fix? I wonder if it’s just the geolocation part?

Thanks

http://wordpress.org/extend/plugins/visitor-maps/