Multiple Public IP Addresses on AWS EC2 (VPC)

Thanks to everyone in advance -

I have an ec2 instance with the following network config: eth0 - internal-ipaddressA eth1 - internal-ipaddressB

public-elastic-ipddressA associated with internal-ipaddressA public-elastic-ipddressB associated with internal-ipaddressB

I configured sshd to listen on both these addresses explicitly: internal-ipaddressA internal-ipaddressB

I can ssh to public-elastic-ipddressA and then ssh to internal-ipaddressA AND internal-ipaddressB, just to make sure sshd is working correctly on both addresses.

All that said, I am unable to ssh to public-elastic-ipddressB if it is associated with any other network interface besides the primary, which was created by default when the instance was started.

Am I missing some sort of special routing or ACL/security configurations here?

Thanks!

Sam