By the way, I ended up with the following code. Thanks for helping.

Jan

CREATE TABLE #tmpADUsers

 (  employeeId varchar(10) NULL,

  SAMAccountName varchar(255) NOT NULL,

  email  varchar(255) NULL)

GO

/* AD is limited to send 1000 records in one batch. In an ADO interface you can define this batch size, not in OPENQUERY.

Because of this limitation, we just loop through the alphabet.

*/

DECLARE @cmdstr varchar(255)

DECLARE @nAsciiValue smallint

DECLARE @sChar char(1)

SELECT @nAsciiValue = 65

WHILE @nAsciiValue < 91

 BEGIN

  SELECT @sChar=  CHAR(@nAsciiValue)

  EXEC master..xp_sprintf @cmdstr OUTPUT, 'SELECT employeeId, SAMAccountName, Mail FROM OPENQUERY( ADSI, ''SELECT Mail, SAMAccountName, employeeID FROM ''''LDAP://dc=central,dc=mydomain,dc=int''''WHERE objectCategory = ''''Person'''' AND SAMAccountName = ''''%s*'''''' )', @sChar

  INSERT #tmpADUsers

  EXEC( @cmdstr )

  SELECT @nAsciiValue = @nAsciiValue + 1

 END

DROP TABLE #tmpADUsers