Hoary md5sums mismatch?

[H Postma]

I just started getting these errors using apt:

http://archive.ubuntu.com/ubuntu/dists/hoary/main/binary-i386/Packages.gz:
MD5Sum mismatch
http://archive.ubuntu.com/ubuntu/dists/hoary/main/source/Sources.gz:
MD5Sum mismatch
http://archive.ubuntu.com/ubuntu/dists/hoary/universe/binary-i386/Packages.gz:
MD5Sum mismatch

What's going on? Did something change in the archives? Are theyt compromised? 

Thanks, Henk