At the site http://digipulse.nl I found a nice article about the configuration of the Windows Server 2008 Core Version.
Edwin, author of this site, describe the configuration over the commandline. Great job!

Configuring an IP address
 
At a command prompt, type the following:
netsh interface ipv4 show interfaces
Look at the number shown in the Idx column of the output for your network adapter. If your computer has more than one network adapter, make a note of the number corresponding to the network adapter for which you wish to set a static IP address.
At the command prompt, type:
netsh interface ipv4 set address name=”" source=static address= mask= gateway=
Where:
ID is the number from step 2 above
StaticIP is the static IP address that you are setting
SubnetMask is the subnet mask for the IP address
DefaultGateway is the default gateway
At the command prompt, type:
netsh interface ipv4 add dnsserver name=”" address= index=1
Where:
ID is the number from step 2 above
DNSIP is the IP address of your DNS server
Repeat step 4 for each DNS server that you want to set, incrementing the index= number each time.
Verify by typing ipconfig /all and checking that all the addresses are correct.
 

Configuring a server name
 
To change the name of the server
Determine the current name of the server with the hostname or ipconfig /all commands.
At a command prompt, type:
netdom renamecomputer /NewName:
Restart the computer by typing the following at a command prompt:
shutdown /r /t 0

 
Enabling remote RDP connections
 
To manage a server running a Server Core installation by using a terminal server client On the server running a Server Core installation, type the following command at a command prompt: 
cscript C:\Windows\System32\ Scregedit.wsf /ar 0
This enables the Remote Desktop for Administration mode to accept connections.
BTW, in order to view your current settings you can type:
cscript C:\Windows\System32\ Scregedit.wsf /ar /v
If you see “1″ in the script output, that means that RDP connections are denied. If you see a “0″, they will be allowed.
Note: If you are running the Terminal Services client on a previous version of Windows, you must turn off the higher security level that is set by default in Windows Server 2008. To do this, type the following command at the command prompt:
cscript C:\Windows\System32\Scregedit.wsf /cs 0
To enable remote management from an RDP connection through the firewall To enable remote management from any MMC snap-in, type the following:
netsh advfirewall firewall set rule group=”Remote Desktop” new enable=yes
To open an RDP session with the Server Core machine On the remote management computer, click Start > Run, type mstsc, and then click OK.
In Computer, enter the name of the server running a Server Core installation, and click Connect.
Log on using an administrator account.
When the command prompt appears, you can manage the computer using the Windows command-line tools.
Note that while you’re logged on to the server, the original server console session is locked out.
When you have finished remotely managing the computer, type logoff in the command prompt to end your Terminal Server session.
 
 
Enabling remote shell management
 
To manage a server running a Server Core installation by using the Windows Remote Shell
To enable Windows Remote Shell on a server running a Server Core installation, type the following command at a
command prompt:
WinRM quickconfig
Click Y to accept the default settings.
Note: The WinRM quickconfig setting enables a server running a Server Core installation to accept Windows Remote Shell connections.
On the remote computer, at a command prompt, use WinRS.exe to run commands on a server running a Server Core installation. For example, to perform a directory listing of the Windows folder, type:
winrs -r: cmd
Where ServerName is the name of the server running a Server Core installation.
You can now type any command that you require, it will be executed on the remote computer.
 
 
Activating the server

To activate the server
At a command prompt, type:
slmgr.vbs –ato
If activation is successful, no message will return in the command prompt.
To activate the server remotely
At a command prompt, type:
cscript slmgr.vbs -ato
Retrieve the GUID of the computer by typing:
cscript slmgr.vbs -did
Type:
cscript slmgr.vbs -dli
Verify that License status is set to Licensed (activated).


Joining a domain

To join a Windows 2008 server to a domain
At a command prompt, type:
netdom join /domain: /userd: /passwordd:*
Where:
ComputerName is the name of the server that is running the Server Core installation. DomainName is the name of the domain to join. UserName is a domain user account with permission to join the domain.
Note: Entering * as the password means you will be prompted to enter it on the command prompt window in the next step. You can enter it in the initial command, if you wish to.
Note: Note that the word “passwordd” has 2 d’s in it…
When prompted to enter the password, type the password for the domain user account specified by UserName.
Restart the computer by typing the following at a command prompt:
shutdown /r /t 0