I don't know why WP Socializer doesn't support Hubmesh.com social bookmarking while its one of the most favorite bookmarking sites among webmasters because of its features like fast indexing and being dofollow.
Please add it to the supported sites.
I see a webmaster tools page on that website that offers external submission option too. I think it helps you to add this service to your module. Please have a look at it here: http://www.hubmesh.com/content/webmaster-tools