It sounds like you're using the JomSocial Profile plugin, but our plugin can't find JomSocial properly. Is JomSocial installed and working on your site? If not, please disable the JomSocial profile plugin (and any other profile plugins where the corresponding 3rd party extension doesn't exist).
If JomSocial is installed properly on your site and working normally, let us know, as that'd be a very strange error to be running into.
Thanks,
Alex