Why I see 404 when doing sudo aptitude safe-upgrade in my lucid 64 box?

deploy@li167-251:~$ sudo aptitude safe-upgrade
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Reading extended state information      
Initializing package states... Done
The following packages will be upgraded:
  apache2 apache2-mpm-prefork apache2-threaded-dev apache2-utils apache2.2-bin apache2.2-common apt apt-utils 
  base-files binutils bzip2 dpkg dpkg-dev gzip ifupdown krb5-multidev language-pack-en language-pack-en-base 
  language-selector-common libatk1.0-0 libatk1.0-dev libavahi-client3 libavahi-common-data libavahi-common3 
  libbz2-1.0 libc-bin libc-dev-bin libc6 libc6-dev libc6-i686 libcups2 libfreetype6 libfreetype6-dev 
  libglib2.0-0 libglib2.0-dev libgssapi-krb5-2 libgssrpc4 libgtk2.0-0 libgtk2.0-common libgtk2.0-dev 
  libk5crypto3 libkadm5clnt-mit7 libkadm5srv-mit7 libkdb5-4 libkrb5-3 libkrb5-dev libkrb5support0 
  libldap-2.4-2 libldap2-dev libmysqlclient-dev libmysqlclient16 libnotify-dev libnotify1 libpam-modules 
  libpam-runtime libpam0g libparted0debian1 libpng12-0 libpng12-dev libpq-dev libpq5 libssl-dev libssl0.9.8 
  libtiff4 libudev0 libusb-0.1-4 linux-libc-dev mountall mysql-client mysql-client-5.1 mysql-client-core-5.1 
  mysql-common mysql-server mysql-server-5.1 mysql-server-core-5.1 openssh-client openssh-server openssl 
  parted python-apt sudo tzdata udev upstart ureadahead wget xulrunner-1.9.2 xulrunner-1.9.2-dev 
The following packages are RECOMMENDED but will NOT be installed:
  colibri debhelper fakeroot hicolor-icon-theme libatk1.0-data libglib2.0-data libgtk2.0-bin 
  libhtml-template-perl manpages-dev notification-daemon notify-osd ssl-cert xauth xfce4-notifyd 
88 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 85.8MB of archives. After unpacking 1712kB will be used.
Do you want to continue? [Y/n/?] y
Writing extended state information... Done
Get:1 http://security.ubuntu.com/ubuntu/ lucid-updates/main libpam-modules 1.1.1-2ubuntu5 [358kB]
Get:2 http://security.ubuntu.com/ubuntu/ lucid-updates/main base-files 5.0.0ubuntu20.10.04.2 [70.2kB]
Get:3 http://security.ubuntu.com/ubuntu/ lucid-updates/main gzip 1.3.12-9ubuntu1.1 [102kB]
Err http://security.ubuntu.com/ubuntu/ lucid-updates/main libc-bin 2.11.1-0ubuntu7.2
  404  Not Found [IP: 91.189.88.37 80]
Err http://security.ubuntu.com/ubuntu/ lucid-updates/main libc6 2.11.1-0ubuntu7.2
  404  Not Found [IP: 91.189.88.37 80]
Err http://security.ubuntu.com/ubuntu/ lucid-updates/main libc6-i686 2.11.1-0ubuntu7.2
.........