Running Windows Process Activation Service as Domain Account

I'm trying to run the WAS service under a domain account and am recieving the following error when attempting to start the service:

System error 1297 has occurred.

A privilege that the service requires to function properly does not exist in the
 service account configuration.
You may use the Services Microsoft Management Console (MMC) snap-in (services.ms
c) and the Local Security Settings MMC snap-in (secpol.msc) to view the service
configuration and the account configuration.

The platform is Server 2008 R2 and IIS 7.5.  The account has the log on as a service right and is a member of the IIS_IUSRS local group.  Managed service accounts are not an option at this time, although I don't know if that would return any better results.  Has anyone else had any success with this configuration?

 Thanks.