关于debian的升级维护请教

[pangty <pangty@tamobile.com>]

	各位师兄，有问题请教，今天做更新操作，过程及显示错误如下，请问error code(29)是什么错误，如何解决，谢谢！
	sources.list里如下内容各是什么什么意思，其中后两行是从linuxfab.cx那里抄来的，如果我的debian是用来做正式服务器的，那么我应该在sources.list里保留哪几行，请给个建议如何，谢谢！
deb http://http.us.debian.org/debian stable main contrib non-free
deb http://security.debian.org stable/updates main contrib non-free

deb http://http.us.debian.org/debian dists/proposed-updates/
deb http://security.debian.org potato/updates main contrib non-free

执行apt-get upgrade后显示：
Reading Package Lists... Done
Building Dependency Tree... Done
11 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 1634kB of archives. After unpacking 306kB will be used.
Do you want to continue? [Y/n]
Get:1 http://http.us.debian.org dists/proposed-updates/ base-passwd 3.1.10 [15.]
Get:2 http://http.us.debian.org dists/proposed-updates/ makedev 2.3.1-46.2 [25.]
Get:3 http://http.us.debian.org dists/proposed-updates/ modutils 2.3.11-9 [162k]
Get:4 http://http.us.debian.org dists/proposed-updates/ make 3.79.1-1.potato.1 ]
Get:5 http://http.us.debian.org dists/proposed-updates/ telnet 0.16-4potato.1 []
Get:6 http://http.us.debian.org dists/proposed-updates/ telnetd 0.16-4potato.1 ]
Get:7 http://http.us.debian.org dists/proposed-updates/ base-config 0.33.1 [72.]
Get:8 http://http.us.debian.org dists/proposed-updates/ debconf-tiny 0.2.80.17 ]
Get:9 http://http.us.debian.org dists/proposed-updates/ debiandoc-sgml 1.1.44 []
Get:10 http://http.us.debian.org dists/proposed-updates/ libtabe0 0.1.7-0.1 [17]
Get:11 http://http.us.debian.org dists/proposed-updates/ locale-zh 0.9+0.05-4 []
Fetched 1634kB in 1m59s (13.7kB/s)
72% [Scanning packages]Template does not contain a Template: line at /usr/lib/p.
E: Sub-process /usr/sbin/dpkg-preconfigure --apt returned an error code (29)
E: Failure running script /usr/sbin/dpkg-preconfigure --apt



Best Regards

pangty
Email:sdyyy@sina.com