cryptographic keys should be regenerated during installation

[Alon Swartz]

TurnKey appliances are vulnerable to a cryptographic weakness due to the usage of non-secret private keys.

This allows an attacker to effectively subvert encryption: decrypt traffic, perform man in the middle attacks, etc. Very bad news for a
system that relies on that encryption to survive in a hostile public network.

[Alon Swartz (alonswartz)]

Fix included in all appliances of the 2009.02 release.

Those using older versions are encouraged to manually regenerate their cryptographic keys
http://www.turnkeylinux.org/content/manually-regenerating-cryptographic-keys