The spec says:
"For Windows Server 2008, Windows Server 2008 R2, and Windows Server
2012, the EncryptedLicenseInfo variable (part of the Server Upgrade License PDU) sent by the server
to the client has the wBlobType parameter set to value BB_ENCRYPTED_DATA_BLOB (0x0009). For
Windows Server 2003, the value of wBlobType is not defined."
So don't enforce the message type.