How to add multiple NetBIOS names to Windows servers

You can add another NetBIOS name in the

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters

section of the Windows registry by adding the

OptionalNames string value.

If three or more NetBIOS names are required, use the multi-string value with the same name.

This NetBIOS name is not treated the same as the server’s "primary" name. To aid in name resolution add a DNS CNAME record that points to the server’s primary name.

For more info take a look at http://blogs.techrepublic.com.com/datacenter/?p=2593&tag=nl.e071

Another interesting post about this theme is the following:
Multiple names for one computer from Jose Barreto's blog