This has been happening all day every time I attempt to do apt-get dist-upgrade:

The following packages will be upgraded:
  libsmbclient samba samba-common smbclient smbfs
5 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 11.0MB of archives. After unpacking 4096B will be used.
Do you want to continue? [Y/n/?]
Writing extended state information... Done
Err http://security.ubuntu.com feisty-security/main smbfs 3.0.24-2ubuntu1.3
  403 Forbidden
Err http://security.ubuntu.com feisty-security/main smbclient 3.0.24-2ubuntu1.3
  403 Forbidden
Err http://security.ubuntu.com feisty-security/main samba 3.0.24-2ubuntu1.3
  403 Forbidden
Err http://security.ubuntu.com feisty-security/main samba-common 3.0.24-2ubuntu1.3
  403 Forbidden
Err http://security.ubuntu.com feisty-security/main libsmbclient 3.0.24-2ubuntu1.3
  403 Forbidden
E: Failed to fetch

http://security.ubuntu.com/ubuntu/pool/main/s/samba/smbfs_3.0.24-2ubuntu1.3_i386.deb:

403 Forbidden