You could try:
SELECT SERVERPROPERTY('ComputerNamePhysicalNetBIOS')
If that doesn't work, there are SERVERPROPERTY parameters that aren't documented: you might try poking around for some of those and see if any of them help :-).
SQL DBA,SQL Server MVP(07, 08, 09) A socialist is someone who will give you the shirt off *someone else's* back.