Unattended Setup - SQL 2008 R2 - ASSVCACCOUNT="NT AUTHORITY\SYSTEM"

I am trying to get SQL 2008 R2 installed using both the Command line and Config.ini file setup options.

I want to do a fairly standard install, I only want the services to use the Local SYSTEM account.

The credentials you provided for the Analysis Services service are invalid. To continue, provide a valid account and password for the Analysis Services service.

I assume this is failing because I'm not specifying ASSVCPASSWORD option What am I suppose to enter when the account is the built-in SYSTEM account.

Any help will be appreciated.

thanks

ben