Stopping fraud signup goes long away. It stops fraudsters, server abuse and spamming. We recommand that Resellers take appropriate measures for this.
We have integrated http://www.maxmind.com/ with H-Sphere. They provide effective way of checking fraud. Reseller may like to implement their free or paid service.
This is available from the 3rd party tools, after entering your MaxMind ID, a new option will be enabled in the Moderation screen enabling you to do a fraud check on signup information.