I haven't touched sources.list, didn't have to change anything in version 5.0.2.
Is "mirror" equated to something somewhere? Maybe version 5.0.3 left it out...
--- On Mon, 1/25/10, Umarzuki Mochlis <email@example.com> wrote:
From: Umarzuki Mochlis <firstname.lastname@example.org>
Subject: Re: 5.0.3 Apt-Get problem
Date: Monday, January 25, 2010, 11:50 PM
When I try to use apt-get with version 5.0.3 I get the message "Mirror not found".
incorrect or unavailable address specified in /etc/apt/sources.list. Make sure every address is accessible from browser just to be sure.