no SHA512 file in repository for 5.1

[Wladimir Sidorenko <wlsidorenko%gmail.com@localhost>]

Dear all,

Could anybody please tell me, what has happened to the SHA512.{gz,bz2} in
the package repository for 5.1

 <https://class.coursera.org/nlp/assignment/part_results?part_id=3>#ftp
ftp://ftp.NetBSD.org/pub/pkgsrc/packages/NetBSD/i386/5.1/
...
anonymous%ftp.NetBSD.org@localhost:5.1_2011Q3>ls SH*
229 Entering Extended Passive Mode (|||65482|)
150 Opening ASCII mode data connection for '/bin/ls'.
226 Transfer complete.

# Though there is such file in the repository for 5.0

anonymous%ftp.NetBSD.org@localhost:5.1_2011Q3>ls ../5.0/SH*
229 Entering Extended Passive Mode (|||65485|)
150 Opening ASCII mode data connection for '/bin/ls'.
-rw-r--r--  1 601  netbsd  791010 Dec 27 07:23 ../5.0/SHA512.bz2
226 Transfer complete.

Unfortunately this prevents my package manager from updating packages.
Maybe anybody of you knows the reason for absence of that file.

Thanks for any hints.

Kind regards,
Vladimir