It's not an error. On one of my DMZs I translate 172.16.x.x to 10.1.x.x. When we had the PIX, we could access nodes on that DMZ by both addresses from the inside network. When we migrated to the ASA, we can no longer hit the network by 10.1.x.x addresses and are forced to use the translated addresses, 172.16.x.x. This is a problem because users have become dependent on both address spaces. Strange but true.