Changing VC services log on accounts

I recently installed vCenter Server 5.1.0, 799731 on a Windows 2008 R2 machine and I want to change the log on account used during the install for the following VC services.

VMware VirtualCenter Management Webservices

VMware VirtualCenter Service

I created a domain service account and have made this domain account part of the local administrators group on the server running vCenter.  I also went into the vSphere client and added permissions for the newly created domain service account with Administrator role.

If I change the Log On account to the new domain service account for both VC services they will fail to start. 

However, if I start the VMware VirtualCenter Service with the old log on account I can then use the new service account to start the VMware VirtualCenter Management Webservices.

I would like to have both services start with the new account.  What am I missing???

Thanks in advance!