I am using Windows 2003 R2......
CREATE SYMMETRIC KEY CIS_Symmetric_Key
WITH ALGORITHM = AES128
ENCRYPTION BY CERTIFICATE CISEncryptionCertificate
Msg 102, Level 15, State 1, Line 2
Incorrect syntax near 'AES128'.
select @@version
Microsoft SQL Server 2005 - 9.00.3042.00 (Intel X86) Feb 9 2007 22:47:07
Copyright (c) 1988-2005 Microsoft Corporation Standard Edition on Windows
NT 5.2 (Build 3790: Service Pack 2)