Missing Samba after Upgrade Packages

My Old PC is a Debian Linux box. I have not upgraded the packages for a long time. Therefore, yesterday, I run Aptitude to do a mass updates. Today, I find the Samba is removed after the mass updates.

I run Aptitude to figure out the reason. I found the Samba has some broken dependency -- libdb4.1. Then, I search the libdb4.1 on the Web. In the unstable branch of Debian, it only supports AMD64 Architecture. Oh! Some packages in Debian is moving from unstable to stable branch.

So, I edit the "/etc/apt/sources.list" to add the stable repository:

deb http://ftp.hk.debian.org/debian/ stable main non-free contrib

Then run Aptitude and update the package list. The broken dependency problem solve and Samba can be installed.