Every time I run apt-get update, I get the following message (the exact duplicate package is different depending on the last entry in sources.list):
W: Duplicate sources.list entry http://ftp.uk.debian.org/debian/ squeeze/main armel Packages
(/var/lib/apt/lists/ftp.uk.debian.org_debian_dists_squeeze_main_binary-armel_Packages)
If I run apt-get update again, it's fine. What's going on?