(k)ubuntu quality updates

[Luca Ferrari]

Hi all,
I don't know if I'm the only one, but I'm experiencing strange problems in 
software updates. For example, yesterday I issued an apt-get upgrade and this 
morning, after a reboot, my ethernet card was not picking up the dhcp 
address. A quick check shown me that the eth0 has disappeared from 
the /etc/networks/interfaces file!
Moreover, even after fixing this, kmail was refusing to download mails, 
without any problem or warning popup, but simply saying that the were no 
messages. I forced the system to do another update, then rebooted and this 
time the machine worked fine. 
This is not the first time that an upgrade produces problems to me, am I doing 
something wrong?

Luca