[c-nsp] ASA address overloading

[Peter Pauly]

We're moving from PIX's to ASA5550's.

We did a lot of external IP address sharing among several internal networks
like this:

OLD:
global (outside) 100 12.34.56.78
nat (inside) 100 10.99.0.0 255.255.255.0 0 0
nat (inside) 100 10.55.0.0 255.255.0.0 0 0

We have hundreds of internal networks that need to be NAT'ed to a limited
set of outside IP addresses (/24).

On the ASA5550 however:

NEW:
object network alpha-dynamic-nat
subnet 10.99.0.0 255.255.255.0
nat (inside,outside) dynamic 12.34.56.78
object network beta-dynamic-nat
subnet 10.55.0.0 255.255.0.0
nat (inside,outside) dynamic 12.34.56.78

WARNING: Pool (12.34.56.78) overlap with existing pool.

Is it still okay to have multiple internet networks NAT'ed and sharing an
external IP address?