Dear apt-developpers, I already posted this question to debian-devel but received no answer yet: http://lists.debian.org/debian-devel/2001/debian-devel-200109/msg01826.html
In short, "apt-get source" should work for the normal user. But it only does if root has umask set correctly upon (every) invokation of "apt-get update" or does something similar. In my opinion either this behaviour should be documented somewhere or it should be changed. Kind regards, Jens P.S. I did not file a bug report yet because I wanted to ask what the expected (though not documented) behaviour of apt is. After that, I will send in the correct bug report.

