[Debian-uk] HTTP 403 from "aptitude update"

[Simon Waters]

Getting sporadic 403 errors from Debian server running "aptitude update".

Nothing repeatable, in that I can fetch a problem URL

e.g.
  http://security.debian.org/dists/lenny/updates/Release.gpg

 From all IP addresses listed:

195.20.242.89
212.211.132.32
212.211.132.250

But the squid log shows it failed at least once with 403.

Hmm log also has 403 errors from ftp.uk.debian.org -- is that conclusive 
proof it is "my problem" since they are hosted in different places 
AFAICT, or does someone else see something similar?