Didn't work is not very precise. As you are using Debian 4.0, I can imagine 3 scenarios. Your sources.list reffers to oldstable, and you get an error saying old-stable not found, or your sources.list uses etch, and you get etch not found error, or you're trying to use my stable or testing repo in oldstable, which leads you to some unsatisfyable dependencies. Anyway without your sources.list entry and the error message, I can't tell you what's going wrong, and I recommend you to upgrade your system at least to debian stable, as old-stable isn't supported anymore by the debian team.