Create the following registry script in a location they have access to, let's say c:\windows\system32 (or in \servername\netlogon) and name it AddIPLocalIntranet.reg
Windows Registry Editor Version 5.00
I choose a number for the range that was very high, so it would not interfere with any ones you may already have. Use 10000 and 10001. Just edit the IP addresses in the example.
Then create the following batch file to run that registry script in the C:\Windows\system32 directory (or again, the netlogon share) and name it AddIPLocalIntranet.bat
regedit /s C:\ Windows\system32\AddIPLocalIntranet.reg
Add that batch file to any place you want to run it from...logon script, group policy, etc.
I tested this, but in case I typed anything wrong, and it does not work, post back.