Why Can't Add A Specific Group As A Login To SQL Server 2005

Hi,

I am trying to add "Remote Desktop Users" as a login group to SQL Server 2005 (i.e. so they can log into management studio). I get a "Not Found Error" (see below). But it is of course found, because I selected it :-) What is going on here? I see the "Administrators" group and various SQL Server groupls added automatically there, so there must be a way, right?

I know I can add each user in the group individually, but that seems overkill when I can just use the group in which they are contained.

Here is the error I get:

TITLE: Microsoft SQL Server Management Studio
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Create failed for Login 'TESTSERVERRemote Desktop Users'. (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=9.00.1399.00&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Create+Login&LinkId=20476

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ADDITIONAL INFORMATION:

An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

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Windows NT user or group 'TESTSERVERRemote Desktop Users' not found. Check the name again. (Microsoft SQL Server, Error: 15401)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=09.00.1399&EvtSrc=MSSQLServer&EvtID=15401&LinkId=20476

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BUTTONS:

OK
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