Key expiry breaks most D-I Etch RC1 images

The expiration of the Debian archive's signing key for 2006 has broken 
most of the installation media from etch RC1. The only RC1 images that 
should remain usable are the full installation CDs and DVDs, but only 
when used without a network mirror.

Final preparations have begun for the second release candidate of the 
Debian Installer for Etch, and we hope to get RC2 out as soon as possible 
to fix this. However, this is currently still blocked by the fact that 
the kernel cannot migrate to testing due to RC bugs.

In the meantime, if you need to use one of the other installation methods, 
use the daily built images. This will also help us with pre-release 
testing for RC2, so please file installation reports!