I am using linux since Suse 6.0, and always I was using KDE. I don't know
why, I don't like Gnome. Also I am programmer since 1987, mostly on
Microsoft based systems, and I have began programming on Linux since 2001.
In the last few years I am using Lazarus/Free pascal. I have installed
Debian 6.0.4 on a normal, simple dual-core Intel CPU computer.
Trying to use the Debian distro with KDE I have encountered several problems
using network:

- I cannot change the computer's name from the Control Center, I had to
change it manually in the /etc/hostname
- when installing Linux, setting the network settings to DHCP, I cannot
change anything for the default eth0, I can change it only manually in
/etc/network/interfaces
- if I change the network settings manually in /etc/network/interfaces then
NetworkManager will disappear from the Panel, eg. at installation I set
the interface to DHCP and now I have set to static ip address, netmask,
etc... the system will work "perfectly" access the network, internet, but
cannot be seen,
- in the Control Center the default eth0 connection does not appear, but the
NetworkManager uses it and the computer can access the internet
- I can add a new connection in the Control Center, and the new connection
will appear in the NetworkManager, but I cannot make the system to use it
by default this new connection of mine. After booting the system always
will use the originally installed eth0 connection and I have to change
manually to my new connection,
- if I add a new connection as root, then that new connection will be
available ONLY to the root user, and not to the normal user.

The old 3.5 KDE has none of the above problems, everything could be done
from the Control Center and everything was working perfectly.

Can You help me in these problems ?
Best regards
Zoltán

In regards to this, NetworkManager under Debian only controls the interfaces it is allowed to control. When they are controlled/configured via /etc/network/interfaces they are no longer available to NetworkManager I believe.

For sharing connections with NetworkManager, you are looking for System Connections. I am able to create these on my system. It also allows me to set DHCP/Static IP preferences. You are only able to have one default however for each network interface.