Comment 2 for bug 27758

I met some difficulty when installing the -dbg package,could you tell me how to install it?
Msg is followed:
root@ubuntu-2:/home/cqin# apt-get build-dep libc6-dbg
Reading package lists... Done
Building dependency tree... Done
W: Couldn't stat source package list http://us.archive.ubuntu.com dapper/main Packages
(/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_dapper_main_binary-i386_Packages) - stat
(2 No such file or directory)
W: Couldn't stat source package list http://us.archive.ubuntu.com dapper/restricted Packages
(/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_dapper_restricted_binary-i386_Packages) -
stat (2 No such file or directory)
W: Couldn't stat source package list http://us.archive.ubuntu.com dapper-updates/main Packages
(/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_dapper-updates_main_binary-i386_Packages) -
 stat (2 No such file or directory)
W: Couldn't stat source package list http://us.archive.ubuntu.com dapper-updates/restricted
Packages (/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_dapper-updates_restricted_binary-
i386_Packages) - stat (2 No such file or directory)
W: Couldn't stat source package list http://security.ubuntu.com dapper-security/main Packages
(/var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_dapper-security_main_binary-i386_Packages) -
stat (2 No such file or directory)
W: Couldn't stat source package list http://security.ubuntu.com dapper-security/restricted
Packages (/var/lib/apt/lists/security.ubuntu.com_ubuntu_dists_dapper-security_restricted_binary-
i386_Packages) - stat (2 No such file or directory)
W: You may want to run apt-get update to correct these problems
E: Could not open
file /var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_dapper_main_source_Sources - open (2
No such file or directory)