feisty repo disappeared?

[antonello facchetti]

I've got some pcs with ubuntu 7.04 feisty in the lab (edubuntu flavour) 
and i noticed that synaptic gave me not found errors during update.
I tried to find out why by going via browser to the url of the repos:

http://archive.ubuntu.com/ubuntu/dists/

there I found out that there is no more /feisty directory, where you 
find main-multiverse-restricted-universe dirs.
The same in the italian server.

All other releases from dapper on are ok.
What can i do?

TIA
Antonello