Amazon Virtual Private Cloud (VPC) customers can now customize reverse DNS for their Elastic IP addresses

Amazon Virtual Private Cloud (VPC) makes it easier to setup reverse Domain Name System (DNS) lookup for your Elastic IP addresses and improves your email deliverability. A reverse DNS lookup for an IP address returns its domain name and is commonly used by email services to filter out spams. This release improves your email deliverability from EC2 by enabling you to set reverse DNS lookup with just a few clicks and meet a key spam filter requirement.

Source:: Amazon AWS