我无法更新我的 Debian Sid 系统。
运行 apt-get Upgrade 我得到：
maciej@wladyslawa:/etc/apt$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages have been kept back:
gnome-keyring libglx-nvidia-alternatives
The following packages will be upgraded:
antlr apt-listchanges bluez ca-certificates-java cron dbus dbus-x11 debianutils
dictionaries-common grep grub-common grub-pc grub-pc-bin grub2-common gstreamer0.10-packagekit
icedtea-6-jre-cacao inkscape iso-codes libantlr-java libantlr-java-gcj libatlas3gf-base
libbluetooth3 libdbus-1-3 libdbus-1-dev libdbus-glib-1-2 libdbus-glib-1-dev libdjvulibre-text
libdjvulibre21 libgc1c2 libgck0 libgcr-3-0 libgl1-mesa-dev libgl1-mesa-dri libgl1-mesa-glx
libglu1-mesa libglu1-mesa-dev libgnome-keyring0 libnm-glib-vpn1 libnm-glib2 libnm-util1
libogre-dev libogremain-1.7.1 libpackagekit-glib2-14 libpam-gnome-keyring libpipeline1 libsrtp0
mesa-common-dev module-init-tools network-manager network-manager-dev ogre-tools openjdk-6-jdk
openjdk-6-jre openjdk-6-jre-headless openjdk-6-jre-lib packagekit packagekit-backend-aptcc
python-glade2 python-gtk2 python-gtksourceview2 python-openssl python-packagekit rsyslog
x11proto-resource-dev xserver-common xserver-xephyr xserver-xorg-core xserver-xorg-dev
68 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.
Need to get 1,571 kB/121 MB of archives.
After this operation, 2,249 kB of additional disk space will be used.
Do you want to continue [Y/n]? y
Err http://debian.man.ac.uk/debian/ sid/main gstreamer0.10-packagekit i386 0.6.14-2
404 Not Found
Err http://debian.man.ac.uk/debian/ sid/main packagekit-backend-aptcc i386 0.6.14-2
404 Not Found
Err http://debian.man.ac.uk/debian/ sid/main packagekit i386 0.6.14-2
404 Not Found
Err http://debian.man.ac.uk/debian/ sid/main python-packagekit all 0.6.14-2
404 Not Found
Err http://debian.man.ac.uk/debian/ sid/main libpackagekit-glib2-14 i386 0.6.14-2
404 Not Found
Err http://debian.man.ac.uk/debian/ sid/main libsrtp0 i386 1.4.4+20100615~dfsg-1
404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/p/packagekit/gstreamer0.10-packagekit_0.6.14-2_i386.deb 404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/p/packagekit/packagekit-backend-aptcc_0.6.14-2_i386.deb 404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/p/packagekit/packagekit_0.6.14-2_i386.deb 404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/p/packagekit/python-packagekit_0.6.14-2_all.deb 404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/p/packagekit/libpackagekit-glib2-14_0.6.14-2_i386.deb 404 Not Found
Failed to fetch http://debian.man.ac.uk/debian/pool/main/s/srtp/libsrtp0_1.4.4+20100615~dfsg-1_i386.deb 404 Not Found
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
我确实尝试了两者
apt-get update --fix-missing，apt-get install -f
但这并没有多大帮助。
这是我的 source.list 文件：
deb http://debian.man.ac.uk/debian/ sid main contrib non-free
deb-src http://debian.man.ac.uk/debian/ sid main contrib non-free
有人知道我该如何解决吗？