T-SQL (SS2K8) :: Table Valued Function For Active Directory Group Membership

For code reuse, I am trying to get a table valued function to return users of a given AD group name. I can easily get this with hard-coding the group name. But because OpenQuery wont accept parameters, I can't insert my group name there. And because functions can't call dynamic SQL, I can't do it via dynamic sql. I have seen people do it with CLR, but I rather not go that route. I can use a stored procedure + cursor and iterate through each group and store the results into real tables and create a cache, but I rather query Active Directory itself to save space, but I rather do the caching then the CLR. Any approach I am missing on how to do this?

The following works fine:

SELECT DISTINCT sAMAccountName
FROM OPENQUERY(ADSI, 'SELECT sAMAccountName, sn
FROM ''LDAP://OU=SomeOU,OU=SomeOtherOU,DC=SomeDC,DC=SomeOtherDC''
WHERE objectCategory=''Person'' AND objectClass=''USER'' AND memberOf=''CN=SomeGroupName,OU=SomeOU,OU=SomeOtherOU,DC=SomeDC,DC=SomeOtherDC''') a
WHERE sn IS NOT NULL

The following gives me the error:

Invalid use of a side-effecting operator 'EXECUTE STRING' within a function.
CREATE FUNCTION [dbo].queryADGroupMembers
(
@group nvarchar(255)
)
RETURNS @rtnTable TABLE

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